A simple, recirculating hydro setup...

[hydrodude]

Picture of Watering Rings

[hydrodude]

Picture of reservoir.

[hydrodude]

Entire Setup

 

Pics of the drainage will be tonight i cant get a good pic during the light cycle. Because of flash problems.

[Luke Skywalker]

Thanks for the permission nimer, here comes the pm's!!!!

 

Luke Skywalker's MJ Answers.... (Now all we need are the questions!

 

No problem, nimer

 

I personally go with a good liquid hydroponic nutrient and dilute it to about an e.c of between 1.2 to 1.6 in veg,

and then increase to around 2.0 to 2.2 in bloom. As to adding nutrients to the mix pre planting and then going

all the way to bloom? I don't think that's advisable. To do this you'd use a slow-release fertiliser like osmocote

or some such, and while they do come in "9 month" formula's, which would appear to be more than enough, there are some problems with this form of fertilisation. For starters, you can't control the release rate. The fertiliser

is encapsulated in a small bead of plastic or wax or some such, which will break down over the specified period

and release nutrients to the plant. The thing is, the release is affected by the temperature, how often you water,

the rate the plant draws on the nutrients, and so on. So in the field, the "6 month" formula can last as little

as two months in hot, wet conditions and can survive up to 9 months! Because everyone has different growing

circumstances, it's pretty impossible to give hard and fast rules with how much of these slow release pellets

to use. Secondly, these fertilisers, when mixed in, are very hard to flush out of the media. They tend to

stay there even after the heaviest flushing, meaning that you cant get rid of it if you over-do it. And when

it comes to harvest time, we want to have as little ferts in the plant as possible, giving the end product

a much, much smoother and better smoke....And finally, they will always be the same nutrients in the pot

if you want to have the ferts last from start to finish.... What I'm trying to say is, when MJ is in it's

seedling stage, it requires different, and much less, nutrients than it does in the vegetative stage, and

in a different spectrum. Also, when the plant starts to flower and then goes into full resin production,

it requires much more nutrients, and once again the spectrum required is different. Much more P is used

and less N. Finally, if the plant is being used to produce seed, more K is required as well as moderate

amounts of P and low amounts of N. The different spectrums of nutients also carries on into the micronutrients

as well, but any good Hydro Nutrient mix should be complete. So using a fertiliser such as osmocote from

beginning to end with MJ is not really the best way to go.... Because if you give it a good flowering

formula, then it won't grow quite as well vegetatively, and your yeild will be down, likewise if you

use a good vegging formula, you may have great vegging, but the flowering on the plant will be substandard

because the nutrients the plant is looking for just isn't there in the quantities it wants....

 

Whew! Boring you yet?

 

Anyway, like I said at the start, go for a good hydro nutient, starting low with a veg formula and

working up to about 1.6 - 1.8 e.c., and then when pre-flowering starts, change to a bloom formula

and slowly move up to around 2.0-2.2. Every two weeks or so, flush out the pots with ph adjusted

water with no nutrient in it to get out the excess salts in the media. About 4 times the volume

of the container is usually enough, but test it with a ppm meter to be sure. When you reach the

last two weeks of budding, then cease all fertilising and use fresh, ph adjusted water, daily

until harvest. This will get the plant to metabolise the nutrients stored in the leaves and other

cells so that the smoke becomes smoother after drying.

 

I know this was a long post, but I just keep going and going! I hope this has helped you, and

if you have any other q's, don't hesitate to ask....

 

Good luck!

 

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Okay dude, let's see if I can help out....

 

NUTES... Thrive is okay, but I found that when using it you tend to get an incomplete feed. The quality

is such that it's okay to feed your roses and lawns, but if you really want to produce the healthiest plants,

with the least probs.... well, you get what you pay for to some degree. Go down to your local hydroponics

shop, if there's a bunnings around, then you should be able to find one. There are a multitude of nutrients

around, and you can't exactly go into a shop and say, "Hi there, I'm looking to grow some high quality

marijuana, what nutrients would you advise I use?" because that's just not on... Most of the major nutrient

companies produce the nutrient mix in a two part liquid form, which contains everything you need to grow and

bloom your plants. The reason they are in a "Veg a+b" and "Bloom a+b" is because some nutrients tend to

precipitate out of the concentrated solution if all are kept in the same bottle. So they separate out the

Calcium Nitrate and put it in a separate bottle to mix in when making up your watering solution. Mind you,

there are plenty of nutrient formulations out there which have everything in a one part bottle, ready to

go, and these can give great results, but over the long term, and if growing to any scale, a two or even

three part nute is the standard. I personally go with a brand called "Hypergro" by Nulife Technologies, it's

a one part nute, but I haven't had any probs with it that couldn't be attributed to something I else I

had done. This particular one is also quite cheap too... I have used two part nutes before, (Dutchmaster's

pretty good, as well as the Nulife Technologies two parters...) and still do for some plants in my collection

(orchids and herbs...) but there's not that much difference really. This is not to say that you should use

this brand yourself, you should do some hunting around to find what's best for you, price and quality wise,

but it's fairly cheap, and like I said, no problems with it so far...

 

Now, as to the soil transplanting mix, DO NOT GET A SOIL VERMICULITE MIX!!!! Sorry, but I can't emphasise

my dislike of vermiculite enough.... That's just me though, as I had a lot of probs with sedimentation and

sludge in my perlite/vermiculite mix, and when using a media that's as heavy as your average potting mix,

adding something that holds even more water in the mix is not a great idea.... So, what have I used and had

success with? Well, if your going to grow in a soil or organic based media, then get yourself some good

quality potting mix, if you can get one with a minimum of nutrients in it that's good, but even if it has

some trace fertiliser that just means you'll only have to fertilise a few weeks later in seedling growth

than you otherwise would have... Okay, so you've got your potting mix, make sure it's a quick draining one

too, ask for that... Then go down to your local hydro shop or two, and get a big bag of the coarsest perlite

you can find. The 100l bags usually cost something like $40 or so, and you can usually buy smaller bags for

slightly more per litre. Take your pot, if your growing in the same pot start to finish, and if growing from

seed, then use a good big 40 or 50 cm wide pot. Make a layer about 7 - 10 cm deep in the bottom of perlite,

just pour it in and level off. It helps somewhat if the perlite's been washed with ph adjusted water (6.0 -

6.2 or so, no higher than 6.5), as this makes it easier to transfer. Be warned though, it's a lot heavier wet

than dry! So, after you have the bottom drainage layer, then mix together some soil and perlite in a separate

container at about a 50/50 ratio, making sure that everything is fully and evenly mixed together. This mix will

be your soil, or media as it were. The perlite makes for much, much improved drainage and aeration, and the

organic matter will provide a good media for the roots to feed on and get water from. The perlite will substantially

lighten the mix, and it may be a little puffy, but don't compact it, or push it down too much when putting it

in, as there's no point in having a nice, airy media if you just compact it so much water won't get through!

If you have any problems with the perlite rising to the top when you water, you can add a 5 cm layer of straight

soil or mulch on the top. If you do use mulch though, get a good quality dark organic one, and leave a small

gap between the plants stem and the mulch, just to prevent any potential stem rot.

 

Okay, once again I've gone overboard here.... I'm just going to keep going till I get through it though....

 

Okay, now, this mix will need slightly more watering than a straight soil mix, as the drainage is improved

so much, but this mix also has the advantage of being almost impossible to overwater! The perlite layer on

the bottom should take care of any excess moisture in a normal plastic pot. That doesn't mean water everyday

though, just when the media is dry down to one knuckle on your pointer. Water less often in the early stages,

and move it up as the plant starts to gain in size and water needs. If you grow anything else, you should

know what I mean. Watering in the mornings is also the best time to do it, as this allows the plant to wake

up, have a good drink and feed, and by the evening when temperatures begin dropping, there's not too much

moisture around, which can lead to moulds and some insects becoming prolific.

 

Now, e.c. This means Electro Conductivity, and it's a measure of the amount of salts in a given solution of water.

Another way of expressing this is T.D.S., which means Total Dissolved Salts, and ppm, which means Parts Per

Million. These readings are all interchangable, even if they are different figures. The way to measure this is

with an e.c. meter, or Truncheon as NZ hydroponics calls it. This will allow you to accurately measure not

only the amount of nutrients you are adding to the water, but also allows you to read the "background" level

of salts in your water. I cannot emphasise the following point enough, but I'll put it in bold italics to give

you an idea.

 

A truncheon is the single best, and most important tool you can ever buy when growing any plant with liquid fertilisers.

 

The only other thing I suggest you get yourself as soon as possible, even before growing, is a reliable ph tester.

Either an electronic one, which is a little hassle, but highly accurate, or a liquid indicator, which isn't

the easiest to read in small increments, but will give the same result for the same ph, no matter what. The

ph of your media, water and nutrient water mixes is just as important as the concentration (e.c.) is. ph

determines the overall acidity or alkalinity of a soil mix or water/nutrient mix, and this is very, very important

if you want decent plant growth. The range of ph is from 0 to 14 with 7 being neutral, less than 7 acid and

more than 7 alkaline. For every single point difference, there is a x10 effect on the acidity or alkalinity of

that solution. For instance, from ph 6 to ph 5, there is an increase in the acidity of the solution by 10 times,

and then if you go from 5 to 4, then that solution is in turn 10 times more acidic again, making 4 100 times

more acidic than 6.... Do you understand what I'm getting at here? Well here's a pic to help describe it a

little better...ph scale description....

 

 

Now, as to the best ph for MJ, in pure hydro you want to go a little lower, around 5.2-5.8, but if your using

an organic media, then keep it at between 6.2 -6.8 or so. The difference is because of the absence of microbial

activity in hydroponics, which is responsible for the conversion of nutrients into usable forms in soil growing.

So, keep ph at between 6.2-6.5, and you shouldn't go wrong.

If you give me an e-mail to send to, I'll send a pic of the nutrient availablility in soil and hydroponics at

differing ph levels. I can't seem to post a saved file here.... oh well, I guess you get the point about ph anyway, eh?

 

Off track a little here, aren't I? Well, I just want to impress on you that getting an e.c. meter and a ph

meter/indicator may be a little expensive (mostly for the e.c. meter, you can get ph indicator for about $5

if you can't be bothered with an electronic ph meter) in the short term, but the money spent is well, well

worth the effort. I strongly, strongly advise that you get both, particularly the ph indicator right now,

and the NZ hydroponics e.c./t.d.s./ppm Truncheon as soon as possible. The Truncheon has all three readings

on it, and can give you an accurate and reliable e.c. reading on the spot. I love the bloody thing, and

while $120 - $130 may sound like a lot, the money is well spent. This will allow you to work out just what's

going into, and coming out of your plants, and that kind of information is very important to know. This can

allow you to accurately fertilise, because you can take into account the base water levels, and you can read

the salt concentrations of the runoff coming out of the pots.

 

Whew.... I think I've pulled your ear long enough here, I hope that I've helped you out, and that this explains

a few things for ya. Once again, if I didn't make any sense here, feel free to pm me, Also, don't just take my planting mix as being the best. This is just what I use and have found works for my conditions. I live in Perth, so your climate could be very different. You should have a look out there, maybe get a few books on gardening, and see what they say. There are lots of guys here who would advocate completely different methods for soil growing, and personally I prefer the control and speed of hydroponics, to soil growing. But the point is, look around and see what suits you best. There are no rules to growing marijuana, but there are a shitload of tips and methods for getting the best out of your plants. There are probably hundreds of thousands of mj growers around the world, and just as many different ways to do it. There's also no substitute for experience, either, so don't be too dissapointed if your first crop or two doesn't produce pounds of super-high grade weed. Because the growing, nurturing and harvesting of mj, is not one you pick up in one season. As a gardener once said, QUOTE

Most of us need three lifetimes to learn about gardening, and another one to put it into practice.

Now, that's gardening as a whole, I don't know if your just going to grow weed, but the points the same... (I think... )

Anyway, good luck mate, and give us a hoi if you need anything else.

 

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Hi there nimer... Well, I've made it back and I'm here to help... Let's see... One of your pm's asked....

QUOTE

when u did your soil grow what kinda growth did u expierence from day to day? its been 1 week now under the

400wattHPS 18/6 and i only have like 1 inch growth and like 1 node per plant. IS this normall? Cause i have

been looking at peoples 4week old plants that are HUGE!!!!!!!

 

 

Okay, well, there are quite a few variables here. 4 week old plants huh? What strain are they, and do you by

any chance know the sex? Are these plants grown from seed? And how many are there? Oh, and can you give me

the dimensions and other info about your growing space? i.e. air movement, (extraction fans, pedestal fans,

etc...) dimensions of the room/cabinet/whatever, how long they've been in there, what soil mix they were

germinated in and what lighting has been used so far, temperature in the room, and size of plant. You say

that the plant is 4 weeks old, but only been under the hps for a week? So where was it growing before this.

And how big is the plant in total? Also, does the plant look healthy? If it does, and has leaf colour nice

and light green, but no burning on them, and no yellow discoloration, then it will get used to it in time.

Also, if the plant is moved from one lighting method to another, for instance you start the seeds under flouro's

and then put them under the hps when established, there will be a period where the plant adjusts itself to

the new environment. Plants manufacture and use food at different rates, according to the environment, as

well as the genetics of the plant. Radical changes in the environment will usually cause a short stall in growing,

but if everything is done to reduce stress to the plant, then growth should resume quickly, and even become

faster in time. Hydroponics does tend to grow quicker plants, but that's mostly because of increased oxygen levels

at the root zone, and a closer control on the variables than you would get out of a soil grow. Organic growing

has it's advantages, but for really fast growth, to the point of almost staggering, then total hydroponics is the

go. If you are going to go with a soil grow, then relax, growing an inch a week is okay, not bad for a small

plant anyway.

 

Right, next subject....

QUOTE

what brand e.c/ph meter did u buy and where? hydroshop? If u think it is important then i think it is important ;-)

After the PM u just sent me i dont think u are full of shit. at Overgrow all people tell me is go the the FAQ's

which are good but really need some work.

 

 

I have a NZ Hydroponics "Truncheon" e.c./t.d.s/ppm meter. This gives an easy readout, in all three forms, so it's

practically newbie proof. It's self calibrating for temperature too, so all you have to do is dip it in once to

the solution, let it read, then take it out, wait for it to stop flashing, and then when you dip it in again it

self calibrates to the water's temp and gives an accurate reading. All it needs is a clean with a bit of plain

"jif" creme cleanser, don't use the lemon scented because that can be bad for the sensors apparently, but how easy can you get? Seriously, look around for a Truncheon, they cost around $120 to $140 Aud or so, and there's no better tool for growing.

As to the ph meter, well after this q you sent me a pm saying...

QUOTE

i keep on thinking of things to tell/ask u . A friend gave me a ph/ligh/moistness meter it is the type with

two prongs coming outa the bottom. Do u feel these are very accurate or a waste of time?

I also bought one of these a while back, as I couldn't afford an electronic one, but it quickly became defunct.

These types quickly give inaccurate results on the ph scale, and I've compared it many times and it's read

wrong from a week after I bought it. But anyway, there are two options here. You can either get a ph indicator

liquid, Flairform, a hydro company, makes one and it's quite accurate. This gives you a small bottle of

indicator liquid, you take a small 5 - 10 ml sample of the water to be tested, and then add two drops of

the indicator. This changes the colour of the water according to the ph. Yellow being neutral, green and

blues alkalines, and oranges and reds acidic. There are other types which use a powder and liquid mixed

with soil, and compared to a chart, or there are strips of paper which are dipped into the solution to be tested,

and then once again compared to a chart. These three methods all work on the same principles. They use

"universal indicator" to work out the ph of the test solution/soil.... Anyway, you can go with these, which are

cheap but if you're colour blind hard to read, otherwise very simple, or you can go and get an electronic ph

tester... These cost anywhere from $120 upwards... They all require calibration, which means you have to regularly

reset them using a calibration solution, which is of a guaranteed ph value. They are advantageous if going for

full hydroponics, and when using reservoir systems, but honestly, many people have told me they are more hassle

than they are worth. If you want to go electronic, that's fine, and it will give very accurate results, but I prefer

the simple indicator myself, it only costs $5 for the Flairform one, and you should be able to find the liquid

indicators and electronic ph meters, as well as the NZ hydroponics Truncheon (I'm a little biased here, because

the thing is so darn good! ) at any good hydro store. If you live in a capital city, have a look around and go to

more than one store to find out how much they're charging. Look for a store with a good customer service up

front, and you should be okay.

 

Right, well, have I bled your ears out yet? hee hee.... Well, if you have any other queries then just give us a

buzz. Good luck mate.

 

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Well, let me say that I think your doing well so far, looking around for pricing and info is a big plus...

The more you know the easier it is to work out what's wrong when something does. (And believe me, something

always goes wrong, don't let that discourage you, but just be aware of it.... ) Anyway, what the ph guy said

about getting an electronic meter for soil is correct. The only way to determine the ph of a soil sample is

with a soil ph test kit. The information I gave you about the other methods of ph testing should do fine. See if

some of your local garden stores carry any of the liquid ph test kits. If you do think you may convert to hydroponics

in the future, then an electronic meter may make life a little easier, but like I said before, I get along just fine

with an indicator. So, in short, don't worry too much about an electronic ph meter, but if you're growing indoors

and want some more precise control over the nutrient levels in your fertilising and if you want to be able to work

out how much buildup of salts you have, then get yourself a Truncheon. I know I go on about this, but I put off

getting an e.c./t.d.s/ppm meter for about a year into my hydroponics hobby/lifestyle, and after I got it I was

amazed at the amounts of wasted nutrient and stunned at the salt buildup in the soil. A good E.C. meter or equivalent is the best tool a liquid fertilising, indoor grower of any kind can have.

 

On to other things....

QUOTE

400watt HPS

Pedestal fan for circulation and to make the plants stalk stronger.

They were germinated in straight potting mix (yates i think with osmacote)

They grew and were germinated outside so do u think the plants have decided that it is flowering time and thats why there not growing?

 

Okay, that's a good start. I still need a little more info though.... For instance, how far away is the light from

the plants, where are the plants, (room, cupboard, attic? size? w x l x d) and have you got yourself a good thermometer yet? Go out and get one asap if you haven't already. And as to the second bit about being germed outdoors.... Yes, that probably is the cause of the slow growth. This time of year in oz, the daylight hours are less than the dark hours, this means that any plants which rely on long night periods to initiate flowering, (like mj) will be doing just that, initiating flowering. Now, you say these seedlings are only 4 weeks old, yes? And they've been growing outdoors for the first 3 weeks, then under the hps indoors on 18/6 on/off. Okay, now, the plants will be still in seedling stage, if they haven't indicated already. Are there any pre-flowers on them? And how do the leaves look? Are they very thick blades or thin ones, and how many blades are there on the top leaf set? I ask because when mj is in veg, the number of blades on the leaves increases by two with each set, from seed leaves, (the little round ones that came out with the germinating seedling), then the first set, with 1 blade, then the second, with three blades each, and so on until it reaches peak, anywhere between 7 - 15!! Anyway, once the plant starts to flower, the production of leaf matter is slowed, and each new leaf set produced will reduce in number, until the bud is forming and there are only single blades on any leaf.... Did that make sense? Anyway, if you could see if the leaf tip number is reducing, then you can tell whether your plants have "turned" from vegetative to flowering growth. Now, as they are young still, and because you've put them under an extended day length indoors, they will soon start to take off!

The plant will be in vegetative growth, and this is what really sets up your yeild. If your growing from seed, then

you should aim at at least two months veg, maybe as little as 1 1/2 months, to really get the plant ready for flower.

Then your looking at anywhere between 6 weeks for the fastest indica to up to 15 weeks or more for long flowering sativa strains. Due to mankinds influence on the plant though, most modern strains are hybrids, and will flower in 8 -12 weeks, a little quicker in hydro or indoors. So this is long term. I hope you were prepared for that.... If you need any help with cloning I can advise on that as well....

 

Okay, now,

QUOTE

Do u think it would be alright to germinate the seeds in teh 50/50 mixture or should i just do what i have been doing

in the past? germinating in 1`inch plugs then transplanting them.

 

 

1 inch plugs? What are they? I mean, if the seeds like it then I don't see any reason why not.... hmm... one inch

plugs.... you don't mean jiffy pots do ya? Or are you talking about growool? Because growool rocks! (get it? "growool rocks? ahh forget it.... ) Get back to me on that one, but if the seedlings like it, then I can't see why you shouldn't go with what isn't broken....

 

Hope this helps ya! Talk to you soon. Oh, and where did you get the seeds you talked about from? Not only the named strains, but where did the current plants genes originate? Just wondering..

 

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Hi nimer, just got your message. When testing ph of soil, make sure you get a representative sample. Do a couple to be sure that it wasn't just a small pocket of low ph in the mix. But if you've got a lot of organic nutrients in there, then it doesn't suprise me. The thing to do is water your plants with ph adjusted water, (you can get a bottle of ph down, usually strong phosphoric acid so be careful, and add this to your water to bring it down to about 6.2 -6.5, this is where that handy-dandy ph meter you just got will come in handy. Don't overdo it with the phosporic acid, though, just take your time, one drop at a time into a 10l watering can, and test along the way. Once you've worked out how many drops to get to optimal then your laughing. It can pay to check on this every now and again though, as a city's water supply can be variable. But anyway, water with plain, ph adjusted water, and then when you transplant into the perlite/soil mix, then do the same. This will even out the ph and ensure a good environment for the plant.

 

Soil growing is a funny thing, some think that it produces a much cleaner, tastier end product, others just think it

slows everything down, but there's no reason that a soil plant cant produce just as good weed as a hydroponic one. The perlite will substantially improve the air content of the media, and this is what hydroponics has that soil does not, large amounts of air. Soil media can become compacted and lose their "air-filled porosity" (air holes) very quickly, unless it's highly biologically active, (worms, insects and such.) In an indoor environment this isn't common, as there isn't a complete ecosystem to support such secondary life. So you must become mother nature, and thus you add perlite to substantially increase air content at root level. I'm losing track here, aren't I? I think I'll leave it there, I just have to pop out, but when I get back I'll expect an answer to my earlier queries, okay? ! Have a good one, talk to ya soon mate....

 

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Hi nimer, just got back from a lovely dinner, and I'm all ready to help ya out. Okay, now. You were thinking of moving into hydro, yes? Alright. There are several different ways to go, and the concept of "hydroponics" is actually quite diverse in the end systems.

There are a few main types, and I'll go into them here.

1. Nutrient Film Technique or NFT. This is usually a pvc or similar plastic tube, anywhere from 100mm to 300mm wide, and of various shapes in cross-section, like tubular, rectangular, ovoid or triangular. Sometimes the "gullys" are made from something as simple as plastic sheeting over corrugated iron, creating many channels. Another piece of plastic on top keeps the plants in place. Other systems use standard pvc pipes, and strawberry growers favour this type. The principle of NFT is simple. If you supply the roots with a constant flow of a thin film of water/nutrient solution, then the plants can have access to a highly oxygenated, consistent supply of nutrients and water, and the flow of water will also carry away any plant wastes. The nutrient solution is usually stored in a large reservoir and recirculated back to the same reservoir to be pumped out again. The res. will have to be dumped and reformulated every two weeks or so to ensure the spectrum of nutes is good. Using an e.c. meter will also cut down on nutrient wastage. The channels are usually enclosed, raised up slightly on one side to assist with the nutrient flow, and most systems use small, 1 inch diameter "netpots" to support the plant. Some others also use 1 inch "growool" or "rockwool" cubes to do the same job. The use of NFT in growing mj? Well, some growers have had great success with large tables of NFT channels, with individual clones spaced out about 2 ft apart. This kind of system is very complex, however, and requires constant vigilance. If the pump fails the whole system will cease to function, as there will be no nutrient/water flow. And then there is the problem of oxygenation when the plants get older. As the root ball develops, the plants in the channel closest to the feeding end are able to monopolise the oxygen and nutrients from the water. The plants further down get sucessively less and less of both oxygen, and nutes, and this usually results in stunted plants. This problem can be alleviated slightly by using a larger channel, (300 mm for mj, at least, and I've seen bigger used for bigger plants.), and shorter lengths on the channels. But overall, as a method for growing weed? Not bad, but a lot of hassle for the newbie. Lets give it say, 4/10 overall.

 

2. Media based system, a.k.a. aggregate system, gravel culture. This is probably the simplest system of all the hydroponic methods to set up and run. It takes minimal maintenance, and can produce damn fine crops. Media systems are based on just that, using a "media" or soil replacement, which is usually an inert, sterile substance, to take the job of soil in delivering nutrients and providing anchorage for the plant. Media systems can be run in a recirculating system, where the nutrient solution is pumped to the pot from a reservoir, and then drains from the pot back to the reservoir. Or these can be set up as "run to waste" where the nutrient solution is applied to the pot and then no attempt is made to recover any excess nutrient. This second method isn't very environmentally friendly, not to mention watery sometimes! But usually run to waste systems in commercial setups are precisely controlled so that there is no "excess" and just the right amounts of nutrients are added. Of course, this isn't very practical for the average, indoor homegrower.... The recirculating system also has its drawbacks, the nutrient solution can become unbalanced if left for too long between changes, and unless you have an e.c. meter it's very hard to judge concentration. These systems also need periodic "flushing" where you apply about 3 - 4 times the capacity of the pots in fresh, ph adjusted water, and this dissolves the excess salts and washes them away. Once every month is usually enough. Now, as to the media itself, there are lots of types. Just to name a few here; perlite, vermiculite (usually only an additive to others, it's too wet to grow plants in on its own.), expanded clay, which is also known as LECA, hydrotron, hotrocks, and many others, scoria, a kind of volcanic rock, coco-fibre, which is an organic media made from coconut fibre, and then there's always good old growool, in cubes or slabs. Some people even use pebbles and normal gravel, although these can sometimes be contaminated and you really want something to be sterile. Some growers used to use sand as a media, but this is incredibly heavy when wet, and it's hydrophobic, which means that water runs straight through it. This is not conducive to growing good mj.... As to my preference? Well, I've used perlite to great sucess, just make sure that you get a good type that's chunky and coarse, and rinse it out with ph adjusted water too, as the dust can be choking when the stuffs dry. Perlite has great aeration and water holding properties, and does well as a media on it's own or as a mix with other media types. Coco/perlite mixes are fairly good, but the coco is organic in the end, and this has to be taken into account. Some growers use vermiculite as a mix with perlite too, sometimes as much as 50/50. But I don't like vermiculite very much, as I may have told you already. It degrades too quickly and holds too much water. Perlite also goes well in a mix with expanded clay, in ratios from one part expanded clay to ten perlite, all the way to one part perlite to ten expanded clay. I've had good results with about 30% expanded clay, 70% coarse perlite. This allows for extra drainage, but the perlite still holds enough water to do well. Making a media based system is fairly simple, you'll need a pot of some type, and if you want to recirculate you'll have to make sure you only have one drain hole (adequately sized, of course), so you can direct it back to the reservoir. The reservoir can stand on it's own, and then you'll have to top it up with fresh, ph adjusted water, as the plants use water and evaporation takes it's share, (a good lid on the res will help with this, and make sure your res is light proof too, or you'll have algae probs.), usually everyday. Or, you can have a second "feeder" reservoir which will automatically replenish the main "nutrient" reservoir by the way of gravity, (put the feeder res above the nute one) and a simple float valve, which will allow water through when the level in the res drops. This kind of "feeder" and "nute" double reservoir system is probably the easiest to run once set up, you only have to replenish the feeder tank maybe once a week or so with only a couple of plants, and depending on the size. Obviously the bigger the tank, the less often you'll have to replenish it. If you want to know anymore about setting up a recirculating double or single reservoir system then just give me a hoi and I'll go into it in more depth... This is probably going to be the easiest system to get your ears wet with. It also produces excellent weed, as good as any other method.

 

On to the number 3. DWC or Deep Water Culture. This system is based on using no media at all! The roots hang down into a nutrient solution, and this solution is oxygenated constantly by way of an airpump, like the aquarium type. This oxygen, dissolved in the water allows the roots to access the nutrients because without air, roots die, and so do plants. Without the air pump this system does not work. Some people use rafts to hold the plants in place, others use netpots sitting in the lids of buckets. These bucket DWC systems are often called bubblers. These sytems also use the splashing effect of the bubbles of air breaking the surface of the water to also feed and water the plant. This "splashing" can also be acheived with ultrasonic foggers, and some small sprinkler sytems, which then takes you from DWC into "Aeroponics" Don't bother with aeroponics, it's not worth the effort. Now, don't get me wrong, bubblers can produce some great results. With careful control, and attention to detail, DWC will perform magnificently. However, if you can't be there all the time, or you don't think that you have the time or desire to put together and maintain such a system, then don't bother. DWC is touted as "easy" and "simple" when in reality it is actually probably the hardest of the hydroponic methods to master. DWC is not for the newbie! Too much can, and quite often will go wrong.

 

So, what do I think you should go for? (And remember, this is no substitute for your own research, mind.) Well,

I'd have to say that a simple, recirculating expanded clay or perlite media based system would be both the easiest

to get the hang of, as well as the most bud for your buck, so to speak. I setup a small cabinet, 600mm x 600mm x

1800mm under 400w hps last year, and the whole thing, light included, cost me less than $400 to set up. If you take out the light, and some other stuff you already have, then I'd say you'd be looking at around $50 or so if you want to build a simple system yourself. The expanded clay or perlite isn't included in this.. If you want to set something like this up, just pm me and give me an email addy to send to. I'll give you a full list of required tools and items, and we'll see what we can do to get you up and running.

 

Whew!!!! I hope that made sense! Anyway, I'll talk to you soon mate, probably tomorrow, eh? Have a good one....

 

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Hi nimer, the ph should be tested after nutrients are added, and before. Adjusting the ph is usually easier to do if

you've already got your nutrients ready, in solution. Otherwise you would be adjusting the fresh water's ph, then

again testing after adding nutes and then perhaps having to take the acidity of the nutrients into account. So just

fill your watering can, add nutrients, add ph down one drop at a time (that's the phosphoric acid type, mind, and

it's so cheap to get it's not funny.) until you reach the desired level. Which, if in soil, should be 6.0 - 6.5 with 6.2 being the ideal. If growing in hydroponics, though, you should be aiming at between 5.2 and 5.8, with 5.4 ideal.

This is lower because the availability of nutrients through ph is very different for a soil grow, with all the biological

activity included, which are the real nutrient supplyers, and the hydro grow, which is usually kept in a sterile condition, and the nutrient spectrum is slightly different as well to take this sterility into account. (There's very

little or no urea, or ammonium in hydro nutes because there are no bacteria around to break it down to nitrate form, which is the form plants can absorb. As well as this the individual salt composition is different for soil and hydro nutrients. Or at least it should be for good growth.) Now, the thrive will not be appropriate for hydroponics. This nutrient is high in ammonium, and is also very hard to completely dissolve in water. Mix it up and have a look. There's a lot of crud in there that doesn't really dissolve fully, is there? This is an important thing in hydroponic growing. You want to get the best, most complete nutrient solution possible, which means one with no algae, (completely dark reservoir) and complete solubility. If the salts in the nutrient begin to precipitate out of the solution, then the plants wont get these salts. This can lead to nasty nutrient deficiencies and blockages of drains, not to mention the possible toxic salt buildup over time. So, until you can get a good hydroponic fertiliser, don't put the plants into hydro. Because the thrive is shit for hydroponics. I know. I learnt that the hard way.... As to how long thrive will keep pre-mixed? I wouldn't keep it that way. Just mix it up, at low strength mind, if you do use it, as your ladies are young, yes?, and use it as you need it. Leaving it out like that will only cause hassles and precipitation.

 

Now, as to the table, yeah, its good, but only really applies to soil growing. Usefull as they go though. I'll see

if I can track down that soil/hydro ph chart for ya.

 

Good to hear that you're going with the expanded clay, I find that it's probably the easiest method to get going on, and produces excellent results. Hydroponics definitely gives a faster turn around, as the plants usually have better feeding, environments and oxygenation of the roots. Depending on the strain, of course, you can have a plant finished from seed to harvest in less than 4 months. And clones can be less than 2, usually 2 1/2, which is a

great improvement for the indoor grower. Of course, simply growing indoors gives plants a head start, due to

environmental controls, but hydroponics gives your plants everything they need to produce primo smoko..... There are a few different ways to go about setup, and I'll have to tailor the specifics to your area, grow space, etc. But two plants is more than enough to start on. If your starting from seed, then I'd advise germinating about 6 seeds for an eventual harvest of two. This takes into account attrition and sex, and also selection of prime mothers.

Once you have some confirmed females, and they are vegging nicely, then you can consider taking some clones for the next crop. Clones do not require long vegging times and can be flowered at any height. Cloning is fairly easy, but does require some know-how, which you should be able to find. If not, then you know who to ask!

 

I'll e-mail you later tonight with some q's about how you want to go about this, and then we can work on getting

you hydroponicing!! (I don't know if that's a word, but I'm going with it!) Talk to you soon mate.

 

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Gday nimer, I'm getting there with the hydro details, this is taking a little longer than I had thought it might.

I should have that done by later tonight.

 

Okay, on to the temps. Now ideal temps are around 20 - 30 degrees centigrade, with a preference around 25 - 28 or so. This allows for good heating and nutrient uptake. If your measuring temps at above 30 c at the plant height, then either raise the light a little, (for a 600w I think it's 45cm, but then again I haven't used these, so you

should perhaps ask someone else about this.) or improve the ventilation. The air in your now enclosed grow room will rapidy heat up and draw water out of the soil into the air, this can be a problem when it gets out of hand.

Fortunately, the solution is simple, ventilation! Seriously, without good ventilation and air exchange, mj will not

grow very well, if at all. The air quickly becomes stale and the stomata (Air and transpiration holes on plants)

quickly become blocked and ineffective. Just get yourself a good extraction fan, from what some others tell me the

bathroom fans are ok provided they are well built. But whatever you get, just make sure it can extract all of the

air in cubic meters/feet within a couple of minutes. 5 minutes at most. This will keep operating temps down, and

make for much happier plants, as well. Keep your pedestal fan, (I think you said you had one?) because this is great for simulating wind in the growroom, which is necessary to build strong stems. Have a look around ozstoners and find a topic on ventilation. I started one not that long ago.

 

Now, the rain water question. Well, there could be a few different reasons as to why the ph of the water would shift over time. To start with, is the container light proof? Got any algae in it? This can affect the ph as the algae use nutrients in the water. Yes, there are still nutrients in rainwater, just not many, and that also depends on where you live. Obviously city rain will contain a lot more shit than rain in the middle of nowhere. Plus, the container you are putting the rainwater could be affecting it, if it hasn't been cleaned thouroughly before filling. I would stick with tap water, just because it's easy and plentiful, and you don't have to rely on the vagaries of the weather. But these are only a couple of possible reasons, once again, why don't you start a new topic on the boards here and see what some others say?

 

As to getting another light, well, if you've got a 600 now, you would probably do better to forget about the plants

in soil if your getting clones for the next grow, but if you want to run the two systems side by side, feel free.

Keep an eye on any contamination of the hydroponic system if you have soil plants near-by, in the form of loose dirt or runoff. If you can manage growing two different growing systems under one light, go for it. Personally, I think the hydro will keep more than enough of your time used up without having to deal with soil plants too. And you should be thinking of getting an e.c. meter before getting another light. Of course, this is all just IMHO so ask around, you may get another opinion.

 

Talk to you soon mate. Probably later tonight.....

 

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Hi nimer! I'm getting there with your hydroponics design, and I'll have that done by late tonight, hopefully! Thanks for your patience mate, it's an essential virtue for gardening of any kind!

 

Now, as to the pumps, well, for the design you are looking at, which will be a two plant hydro dual reservior, then

you'll want at least a 600l p/h nutrient pump (pond pumps, the ones that push water! ) with around 1200 l p/h being the max you'd require. If you get the larger pump, you'll have more head height, (the distance the pump can move water vertically) and you wont have to irrigate for as long to get the same amount of water through the system. If you look around you should be able to get a good brand name pump for between $40 to anywhere up to $80 or even more. Now, I've just had a quick look at the pumps available at grow.com.au, an okay internet hydro shop, and they have a rio submersible pump at $40 for the 800Lp/h to $65 for the rio 1700Lp/h. Now, that's just one supplier, and of course there's postage costs with that, but if you look in bunnings or your hydro shop, or even aquarium shops, you should be able to find an appropriate pump. Of course, you pay for what you get, and rio is pretty much the industry standard, although there are many companies making comparable products.

 

Okay, the air pump. Air pumps are cheap as chips. Of course, once again it depends on the size of the containers and so on, but you shouldn't have to spend more than $30 for a good one. You will only be using the air-pump to aerate the nutrient solution in the nutrient reservoir. This will give the plants a good supply of highly oxygenated solution when watered, and will also help to keep algal growth and various other nasties from establishing. This isn't a necessary purchase, but they are worth their money, and I would recommend you get one. You'll also need to get some 4mm line to transfer the air and an airstone to ensure that there is maximum contact of the air with the solution. Lots of bubbles in otherwords.

The lamps. Sorry about the confusion there, I have a feeling it's my fault. Now, I would honestly advise you to put

off the purchase of a second lamp until you are absolutely sure you are capable of setting up two grow rooms. Or you could use the 600w to illuminate the grow, and this would allow you to get a bigger yeild, as well as 600w lamps being the most efficient electricity wise. $200? That's quite cheap! Is this a second hand one? Because the lamp itself can cost a lot to replace if the second hand one that comes with the setup is old, or damaged in transit. So make sure it's a new, or very recent bulb, and ask to see it in operation if it's second hand. This is once again all IMHO, but I think the 430 w son t will do you okay for now, unless you are serious about setting up a veg and flowering room. (Another discussion for another day.... )

I hope that made sense, and once again I thank you for your patience. I'm not very good with drawing on the computer (we only have paint) and I'm having trouble putting the pix together. But I will have it together soon. I promise. If you have will, time and effort required to grow yourself some quality indoor weed, then I've got the will, time and effort to help teach you. I hope your looking around for more than one source of info, though, because what I know more than anything else about gardening, is that there is a shitload of different ways to grow great indoor weed, (not to mention the old fashioned way!) and most, if not all of them are perfectly usable for the average joe. So see what some other people say too dude, because I'm only a fellow grower, and there are many others out there like me! Don't take this the wrong way, though, I'm still more than willing to help ya! All ya have to do is ask!

 

Talk to you soon mate.

 

I wish I had a digicam... rassum frassum....

 

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Hi nimer. Well, let's see if we can't help you out, eh? Okay, now for the reservoirs, I use the 60 or 80 L clear

storage crates, and then I cover them with panda film, (the black on one side, white on the other side plastic

sheeting you can get from hydro shops.) to make them light proof. You could also paint these, but you'll have to buy a plastic treatment before you do so, so that the paint sticks. The treatment costs about $20 for the larger tin, but I've heard that its really good. You can also get plastic barrels from hydro shops, between 100 and 250 L, and you could also use a plastic garbage bin, you know the black lids with green bins? The ones people used to use before wheelie bins? Anyway, some growers use these and have no problems, but obviously, you'll have to make sure it can withstand the pressure of being filled with water. Any of these could be used as reservoirs, but the main points about choosing one, should be the size, as more solution changes less quickly, sort of like a buffering effect, and the other thing is lightproofing. This is essential, as any light will cause algae and other nasties to start growing in the res, which will quickly use the nutrients and block pumps and piping. If you can't get an opaque reservoir, then just use panda film.

The 200mm 20l buckets you found should do the job, the reason I said 400mm was I was referring to the black plastic pots that you get most potplants in, and you can get ones from hydro shops without any drainage holes in the bottom. Provided that the bucket is 20L, I can't see any probs for you, but you may have to place the drain hole a little higher to compensate for the tall, narrow shape of the pot. You can get white buckets from your local bakery, their used for margerine and jams. If you ask really, really nicely they may give them to you for free, but they may charge a couple of bucks each for them too. Ask around places like this, and you should find somewhere willing to part with their old containers. Of course you must make sure that the container is totally clean, otherwise you'll run into problems down the road. Wash it out with normal detergent and hot water, then rinse out thouroughly, and maybe even sterilise them with a mild bleach solution, rinsing again afterwards.

 

Talk to you soon.

 

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Well, it all depends on if you plan to expand anytime soon or not. I think you meant that you have 4mm, not 6mm line, correct? You couldn't find the 6mm, which doesn't suprise me as I can only find it at my fav hydro shop. Okay, now if you get the 1700, I would probably go with a 13mm line for feeding, but make sure that when you set it up, that you can get enough pressure in the 13mm line to get water to the plants. If you can't get enough end pressure, then just reduce the size of the feeding outlet with an adaptor to reduce to 4mm, or change half of the feeding line so that the water initially goes out into 13mm, then halfway reduces to 4mm to increase pressure. This should give you the pressure you'll need. If you go for the 1700, you will probably only have to water for a couple of minutes each feed, as the rate of flow will be more than double the 800, so be aware of this.

 

Go for the 1700. Better to have too much pumping ability than too little, eh?

 

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Well mate, hmm, bunnnings doesn't have any adaptor pieces? Do they have much of a retic section? Maybe look around for a reticulation/irrigation shop, they have pretty much every piece of black polypipe that you can think of!

Overwatering? Yes, even in hydroponics this is possible, although thanks to the media it is a bit harder to do this

than in soil.... But still possible. Remember what I said about irrigation times? You should be watering for long

enough so that water starts to trickle out, and then start to measure the volume coming out that drain as the pump runs. When the amount draining out reaches about 20% of the total pot volume, then that should be about how long you water for in each irrigation. It's unfortunately one of those things that's dependent on your system and environment, and there are no hard and fast answers. When you have young plants, just water 2 or maybe 3 times a day, but of course if the plants look like they need it, then give them some more. As the plants grow older and the daylight time reduces, from 18 to 12 hrs, then you can move the irrigation cycle up, maybe to 4 or 5 times a "day", when the lights on, for however long you need.

 

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Hi there nimer, well if you've got the pots I think you have, then just make the drain hole come out at about 4 or 5 cm from the base of the pot. Make sure you put the "T" or "L" piece in watertight too.

 

Now, to your earlier queries...

 

QUOTE

OK i got my pots from the bakers this morning but i dont think there big enough they look like there only 10litres..... IS it possible to transpant a plant that has been established in expanded clay? If not then i will have to get larger pots.

 

Yes, it is perfectly feasable to transplant a plant which has already become established in expanded clay, just be

gentle with the root ball and try to disturb it as little as possible. And it can help to raise the lamp a little while

it gets used to its new home, this will reduce stress. After growth resumes, (if it stops or slows, that is, if you do

it well enough it shouldn't stall at all.) you can return the light to the original level.

 

QUOTE

Why would it be bad for the plants if 100% of the total pot volume was waterd in a session? i am not going to do it but i was just wondering what it would do to the plants.

 

Well, the 20% figure is a general one given for most recirculating systems. This allows for a good exchange of nutrients and flushes out the old salts which are left on the media. If you were to increase this runoff to 100%, you may have some problems with overwatering, but in a media like expanded clay this is unlikely. It's a matter of watering enough to feed and flush the plants, but not so much as to drown and damage the roots. But like I said before, overwatering is a difficult thing to do in a media like expanded clay. Just stick with the 20% runoff, and you should do okay. If your plants need more often or more feeding, then by all means, do so, but this should do you okay. There'll be a small reserve of nutrient at the bottom of the pots, remember to put the drain piece about 4-5 cm above the base of the pot. This will ensure that should everything go cuckoo, your plants will still have something to feed off.

 

QUOTE

After each watering does the expanded clay stay moist? does it hold any water?

 

Expanded clay does wick water to some extent, but nowhere near the levels that some other medias do, so it needs to be watered a little more frequently than perlite or soil. The expanded clay holds moisture on the uneven surface of the pebbles, within the pebbles themselves, and in the gaps between them. If you were to run a system using expanded clay and no mini-reserve at the bottom of the pot, then you would be watering much more often. This may not sound good, but in actuality most growing media are only restrictive to plant growth because it doesn't have enough air in it. Air-filled-porosity, they call it. Expanded clay has a fantastic level of oxygenation to it, because of the size. So consequently, if the media is watered regularly enough, it can be an awesome media.

 

QUOTE

I am going to be building my watering rings tonight as well as everything else so i will post some pics afterwards.

Sorry about all the questions mate :-D

P.S have u taken alook at my current soil grow? i ahve a grow journal in progress...

 

I'll look forward to it mate, and I'll check out the grow soon. Don't worry about asking questions, I'm more than willing to help you out if you're willing to learn. Have you had a look at any hydroponics books from your local library yet? They can be a fantastic source of information, even in this electronic age....

 

Talk to ya soon, bud.

 

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One drop every couple of minutes shouldn't be a problem, after all, the thing isn't going to be filled with water,

it will be filled with mostly expanded clay. If you can wrap a little gaffa or cloth or even electrical tape around

the end of the "L" or "T" piece that goes into the pot, this should provide the seal your after. Post some pics if you

can on your grow post and we'll see how your going, eh?

 

Oh, and I think I may have neglected to answer one of your q's about heating the nutrient solution. This should only be necessary if the temp in the nute tank gets below 21 c or so, with the ideal temp being 24. This temp ensures that the nutrients in solution are in plant available forms, and that there is no sedimentation or precipitation in the solution. If you have any probs with this, let me know.

 

Uhm, as to RIO pumps, well, that's just the standard brand, and they are pretty much what everyone compares to. Where to find them, well, you could look at bunnings, they usually have pond pumps, and some pet shops have them too.... Grow.com has both RIO and other branded pumps available, and you can pay by cash through national bank, which makes for better security. There's also a company selling hydro gear dirt cheap, a fellow grower here passed on the link to me, how's $32 for a new 400w hps globe sound? Thats about as cheap as you'll ever find it. They sell lots of other hydro gear too, so you may find some of what you want there. They're called Simplegrow Hydroponics, and here's a link. Simple grow....

 

I hope that helps.

 

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Just joking mate, I know it's hard to put sarcasm into a text message. Anyway, pH!

 

Now, I'll be honest with you here, this is a bit of a contentious issue amongst some. I personally subscribe to the

5.2 - 5.8 range, (for hydro, anyway) where as some others will say 6.0 - 6.8 or so... The thing is, ph is a little

more complex than simply, "this is the perfect level, no matter what you use..." And I'll explain.

 

Hydroponic systems operate on different principles to soil growing. When you grow plants in organic mixes, otherwise known as soil, the mix slowly breaks down as small bacteria and other microbial life starts to convert the complex organic molecules into simple, chemical forms. The addition of organic fertilisers feeds these microbes, which in turn feed the plants. Have you ever heard the saying, "feed the soil, not the plant."? It's quite accurate in soil and organic growing. The amounts of nutrients a plant can absorb is entirely dependent on the chemical form of these nutrients. And at different ph levels, the salts we want start to become "locked" up in the soil, because the ph level has caused an undesirable chemical conversion to occur, which changes them into different, and therefore unabsorbable forms. To ensure that this doesn't happen, soil growers try to keep ph in the 6.0 - 6.8 level, 6.3 or so near ideal, and whilst you will still get growth outside these levels, it won't be anywhere near it's real potential.

 

Hydroponics, however, is a different story. Instead of relying on microbial life to convert complex organic fertilisers

into absorbable forms for the plant to use, we simply supply the absorbable form in a nutrient solution, and this

is directly used by the plant. The plant doesn't know the difference, (aside from bein

[hydrodude]

Well anyone should be able to read this thread from start to finish and be able to start a crop :-D

 

Looking good luke

[Buster]

Holy Moly!!

 

Theres loooooads there, I was scaning down through the page and thought it was the matrix!!!!

 

I'll have to read a bit at a time me thinks.

 

 

Buster.

Edited May 28, 2003 by Buster

[hydrodude]

Yes he did write everybit of it :-) i couldnt belive it when i would write him like 1 paragraph of a questions or 2 and get 2 pages of info back :-D

 

 

What a mentor!

[Luke Skywalker]

Knowledge is power.... Learn all you can from whoever will offer it.

[karzon]

With this setup, does the water/nut run constantly or is the watering timed with timmers? If so, what is the timming.

 

Thanks a bunch!

[Luke Skywalker]

The nutrients are pumped to the pots through a timer, which can be set up to water according to your conditions. For instance, if you were using the expanded clay media, you may have to water for 15mins every couple of hours or so, but you may have to do so more if it's warmer... it's really the plants themselves and the environment which will determine how often you're watering... If you were using perlite you could probably stretch out intervals between irrigations a bit, and even more if you used a more water retentive media like coco or growool. I don't water during the dark period.

 

The best advice I can offer for each persons setup is to ensure there is an adequate run off of nutrients with each irrigation. About 20% of the volume of the pots in runoff is a good level, but once again it depends on the media/setup/environment. If you can get a 1min increment timer you're much better off, as opposed to the 15min/30min increments on the cheapo ones.

 

And one more thing, every two weeks you need to flush the media with fresh, ph adjusted water until the water coming out of the pots is testing at the same or near the same e.c. as the water going in. This flushes out the excess salts which accumulate over time on the media surface...

 

Hope that helps.