Flushing ....

[postman]

Ramakrishnaswamy can write 25 alphabets on a single mustard grain , In fact, over two thousand years ago, someone managed to write two hundred symbols on a single grain of rice using a strand of hair.

 

It is still exhibited in the Topaki Palace museum in Istanbul, Turkey.

[Frazz]

Ramakrishnaswamy

 

 

LMFAO ... yea, but he/she didnt know how to grow weed did he ?

 

 

EDIT: hey, didnt that Ramakrishnaswamy dude play footy for Essendon?

[blacksaint]

Frazzle, in regards to Canna, I think you'll find they are now recommending much lower EC levels for their nutes. Nothing above about 1.8 in full flower.

I followed these levels on my first grow and got good results.

 

In regards to this topic, I'm too inexperienced to offer anything profound.

I've settled on flushing my pots once a week, and the res every 2 weeks, whatever the system.

 

I'll certainly be following this topic though, as it turns on its head some of the basics I held as true.

[Frazz]

Yea thanks Blacky ... i was wondering about that as i have Canna Vega that says " We advise an EC of 1.8-2.7 mS(=EC " ... ???

 

So does anyone know what the "2.7 mS(=EC" really means ... or is it yet another way of measuring the Salts??

 

BTW Canna Vega also says " rinse with water every 1 to 2 weeks" ... wow

 

most interesting topic

[Taipan]

Yea thanks Blacky ... i was wondering about that as i have Canna Vega that says " We advise an EC of 1.8-2.7 mS(=EC " ... ???

 

So does anyone know what the "2.7 mS(=EC" really means ... or is it yet another way of measuring the Salts??

 

BTW Canna Vega also says " rinse with water every 1 to 2 weeks" ... wow

 

most interesting topic

the 2.7 ms is a way of measuring the salt content. The correct measure is ms/cm2 or milli siemens per centimeter squared. To fully understand this you need to do a science degree, you don't really need to know what it means, it is just a level of measuring the nutrient content used in hydroponics. Basically ms/cm2 is called EC (electrical conductivity), another scale used is CF (conductivity factor) which is EC x 10. So no decimal point. Another scale used is ppm. It can get a bit confusing but converting ppm to EC or CF and back is not as simple as people may think. There are exact conversion factors for each individual chemical, but not necessarily for a nutrient blend. The hydroponic industry decide to average out the different ingredients and came up with a conversion factor of 65 although some companies use 70, although the US use different conversions. It doesn't matter a lot, what it means is that ppm =(approx) CF x 65. All rather boring stuff.

 

What I was trying to point out in my original post is that flushing your growing mediums with fresh water is not considered good practice in the huge world of commercial hydroponics. It can shock the root zone and stress the plant. It obvisously doesn't cause any major problems as most people do it. If you need to flush, a weak nutrient solution is more advisable than just plain water.

 

The other point I was trying to make, not that I really voiced it, is that the nutrient content of the growing medium is the most important thing. Depending on the system or the medium you use, the strength of nutrients in your tank may vary a lot from the strength within the growing medium. This is where flushing may become important if the nutrients build up in the growing medium. But if you manage your system correctly they should not build up in the medium. And this is usually achieved by feeding the plants with weaker solutions. It does not mean they are missing out on anything.

 

I think frazzle got it right with regards to most companies recommendations, they want to sell more nutrients, so high dosing and regular flushing will achieve that. Personally I have had much better results when feeding a lot weaker which removes the need to flush.

Edited February 1, 2007 by Taipan

[loylty gets u nothing]

i use me canna nutes at 2ml per litre

that way im happy the plants happy and we have a good base

when i have run dwc i have found it to be beneficial to run 1 day every 10 of plain water...maybe this helps in clearin the salts as pipeman mentioned.imo after this process my plants seemed happier..

im gunna try this method of only flushing prior to harvest..

usually wen i flush anytime before pre harvest flush i usually have the ec at 0.6 and i like to serve me nutes up at 1.4 jump1.6 ec in the summer hand feed daily and i flush fully with a good 80ltrs of water at 12/12 flip...so should i not be flushing between grow n bloom?

 

if u see tip burn is it ok to flush then???

thanks guys

bil

[SukonmiSkunk]

home from work.. and am in a surprisingly good mood..

 

ok... tiapan.. I totally understand what you're saying about never flushing the medium... you also refer to "commercial" growers... youre exactly right.. MOST commecrcial growers will never flush.. even in that final week... this is why we personal growers ..um.. grow our own.. becuase every ounce of commercial grown weed that ive ever smoked has been crap.. making me wheeze after having a cone.. fireworks in the cone while ya smoking and just tasting like shit in general.. no BUD flavour at all... just nutrient tastes...

 

im glad you rectified your post and suggesting a final flush for the last week... so I think we are agreeing with each other here....

 

back flash to the late 80'swhen I first started growing.. a little before SKUNK weed became more prominent... I was one of these so called commercial growers you speak of... me and a good friend of mine had 15 grow ops on the go at once..we had one house decked out just for cloning... im not talking little rooms either... im talking whole houses... upto and beyond 10 1000watters.. with plants in every stage of growth... a commercial set up... now no one lived at these houses.. and it was hard for us to get to each one and do the necessary maintenance .. we had 200liter hearts set up.. with dosers and float valves.. the only time we went to check the crop was at 4 weeks.. to turn the lights back... or shuffle plants around.. depending on the house... then when it was time to harvest.. NO flushing EVER.. just cut and dried then sold... so when you say there is no need to flush.. you are absolutely correct... how ever.. I wouldn't want to be smoking any of that crap.. it did taste like hydro.. it did sparkle when you smoked it.. it did make you wheeze after a cone.. didn't mean we got any less for our pounds... there was no flushing at all during the grow becuase the dosers were set at 1700ppm.. the whole way through...

 

skip forward to NOW... ive learnt a fuck load about growing since those early days... it was explained to me like this... plants take nutrients.. the same as we do.. they process the nutrients.. then expel what they don't need.. ie shit... like we do... you wouldn't like to be walking around in shitty daks would ya?? well neither do plants... this is what we call salt build up.. but really it is just unusable nutrients... so you need to drain the resi.. and replace with fresh water and nutrients.. in most cases this is usually enough.. but its a shit load better to give the plants clean water for a day just to rid the medium of any stubborn... shit..

 

obviously depending on your medium.. depends on how much you need to flush... take hydroton(expanded clay) or versa rock...now they don't hold a real lot of water.. hence why you need to feed more often.. so a light flushing is usually more than enough... hardly needs it at all.. like you say... how ever... take perlite or rockwool for instance.. holds a shit load of water and retains a lot of salt build up... so needs to be cleaned at least every 2 weeks... not just changing the water.. but flushing with CLEAN water.. NO nutrients... youll find if you're running the resi at 16-1800ppm... and then dump the resi for a flush using ONLY water.. you'll notice the PPMs will sit at about 1200ppm.. still a lot of nutrients in there hey.. NO need to flush with a week strength nutrient.. because at 1200ppm.. that is already a weak mix.. so the plants don't suffer at all over the day or 2 that you take flushing... I get my resi down to around 5-600 before I ad nutrients again... like you say.. its probably not entirely necessary but when you taste the difference between NOT flushing and flushing.. you'll be flushing hey...

thats just a regular maintenance thing.. and really only a preventative measure... best to sort out problems before they arise in my book.. you will only get issues from a hydro system if the medium hasn't been flushed regularly.. and nearly every issue Ive come accross has been down to slackness... and not keeping the system running smooth and clean... a clean system will never have issues... I never have issues with any of my crops.. well i haven't for quite some time.. touch wood..

 

salt build up.. ph fluctuation's ...are ALL caused from poorly maintained systems .. clean systems with regular maintenance will very rarely have any plant issues

 

oh no to mention a regular flush helps clean the system too.. stops drippers from clogging as so on...

 

now thats just regular maintenance to keep your system running smooth.. so you don't get any ph.. or salt issues...

oh .. and between every crop.. you should pull the system down.. and wash everything thoroughly.. if this is done then you will have a lot less issues.. and you might be able to get away with not flushing at all through the grow... ive worked in commercial hydro green houses.. designed and commissioned them... now they flush their systems every 3 days... if it wasn't necessary they wouldn't bother im sure...

 

final flushing is a MUST.. even if you've been slack through the whole grow... if you wish to smoke any of your harvest.. you'd best flushing.. now I flush for about 10 days in the final stages... ill explain why...

 

I grow in straight perlite.. in a recirculating system... to get my PPM's down from 1800.. to around 50-100ppm it takes about 4-5 days.. and a fuck load of fresh water... plants only seem to drink water in the final stages anyway.. so its hard to get the ppms down... as they rise when the plant drinks... I need to replace the resi water about 2-3 times a night.. .and only when the light is on... then once my PPMs are down to an acceptable level... ill run the resi at around 100ppm for the final 3-4 days before i chop... ill explain why..

 

it takes about 3 days for the plant to use up any available nutrients left with in the plant...the medium is clean... so when I harvest.. i have MAJOR nutrient deficiencies showing on nearly every leaf.. this tells me.. that there isn't a lot of nutrients left in the plant as it is sucking all it can from the leaves...

my last harvest.. I chopped them out with the ppms reading 90ppm... my rainwater measures at 50ppm... so to me that only leaves about 40ppm of hydro nutrients left in the plant... and I can tell you now... and so will spook.. that this is a fuck load better to smoke than a plant that has been harvested with the ppm's reading about 1800ppm... like we used to when we were young and dumb...

 

so yes you're right when you say you don't need to flush through the cycle... to have healthy plants... how ever a flushing every now and then certainly helps keep the system maintained as well as the plants staying healthy.. or healthier...

 

final flushing is a MUST... especially if you plan on partaking in a choof of your harvest...

these days I grow purely for my self.. as money isn't my reason these days.. and I can say from my experience.. that the shit I grow now.. kicks ass over anything ive ever grown back then...

[Taipan]

home from work.. and am in a surprisingly good mood..

 

ok... tiapan.. I totally understand what you're saying about never flushing the medium... you also refer to "commercial" growers... youre exactly right.. MOST commecrcial growers will never flush.. even in that final week... this is why we personal growers ..um.. grow our own..

Actually I am talking about legit commercial crops. In my own experience I have dealt with and still know quite a few commerical weed growers, but in this topic, when I am talking about commercial growers never flushing I am talking about commercial growers in many countries of the world, Holland, Australia, New Zealand etc that grow food and flower crops hydroponically. Indoor growers may think that there is no relation between the 2, but more knowledge can be gained as far as hydroponic growing is concerned, by looking at what these huge growers do in their systems, compared to what can be learned from a comparitively very small industry world wide, ie growing weed hydroponically. The amount of research that has been done to learn and improve growing methods is staggering and these growers are the people that we should be learning from when we try to perfect our own gardens.

 

I have found that hobby growers are tending to take a different path than these very experienced legit growers and I think that is possibly a mistake. I have read lots of books on growing weed, and none of them have really impressed me with their information on "hydroponics" but I have read some very informative books that commercial food and flower growers pass around. And they have covered many aspects that indoor growers are just guessing about, and could learn from.

 

Not meaning to put you down at all SukonmiSkunk, you have obviously had a lot of experience yourself and have developed your own methods that work very well. And I have learnt long ago there is no black/white when it comes to growing hydroponically under lights.

Edited February 1, 2007 by Taipan

[bufo marinus]

Whoa taipan you sure know how to kick up some dust , hehe. I've been coming around to the use of lower nutes too and have started using a light flush as a way of being able to measure and bring the EC back down to 1.0 (and the pH back up to 5.5)in the coco,... just thinking about it the plants have looked really good the morning/day after

I still sit the res at to 1.6-1.7 and wonder why it only takes a week to build up to 2.0 in the medium hmmm

I've also been using Superthrive when I flush as I thought it would be useful then

[SukonmiSkunk]

mmm pot forum mate... unless you specified about hydro veges.. then we would all just assume.. as EVERY one here has.. that your talking about MJ...

 

at the hydroponic herb farm i used to work at we would flush every three days... thats had nothing to do with the crop.. and had EVERYthing to do with cleaning and maintaining the systems... as for flushing the plant like we do for Mj to rid it of all that hydro/fert taste .. well that doesn't happen...

 

are you in Australia?.. we have VERY strict guidelines as to how food is either grown or killed.. huge scale operations that grow .. lets just say herbs..as this is where I have my experience ..have guidelines on the cleanliness of the systems.. nutrients.. and pesticide sprays... the herb systems were all in a NFT style so the pumps ran 24/7...every time a table was harvested it would be pressure cleaned to blast out all the algae ...and clean the treys for the next planting.. now most herbs would be ready in about 6 weeks.. parsly was about every 4.. very fast in the hot houses... so each table wouldnt even go 8 weeks with out a thorough clean... the tanks were flushed and dumped and refilled with fresh water and nutrients every 3 days.. with out fail.

 

now as for running clean water through the actual system to flush the system like we do for mj.. that never happens as the plants would probably suffer.. this doesn't happen with mj.. for reasons ive previously stated.. ie.. mediums holding a lot nutrients... as well as the plants... as flowers feed from the leaves.. and it takes about 2-3 days for the leaves to show signs of deficiency and recover fairly quickly...and we only really flush for a cycle over 12 hours..during the grow.... until the final harvest.. thats when we give a more full flush medium and plant for taste.. mostly.. but its got to be healthier... to flush, doesn't it?

 

pretty much everything we learn comes from big scale legit operation's..like tomatoes.. herbs.. cucumbers.. and a shit load others... but those were days of old... now there are quite a few legit MJ growers around the world that deal in medical pot.. in the US... in Holland.. in Canada.. and in Sweden.... a lot of other places too.. these places have real scientists.. and botanists.. growing medical MJ for human consumption...

 

as you are aware everything in the food and drug industry is closely scrutinized to make sure its safe for human consumption.. pesticides have withholding periods to make sure the toxic levels have subsided low enough so the product is safe for human consumption.. I would say this would have to apply for MJ as well... we all know about the dangers of spraying for bugs when we are flowering and how we need to wash the residue of the buds before we smoke it...

 

so if you're saying we can learn a lot from big scale legit hydroponic crops.. and use that for MJ.. well we did that.. and have moved on... now there are techniques being used world wide to enhance flavor and yields... .. but the best advice I can give to anyone... is maintain a healthy system and grow environment.. the plant will grow it self...pretty much... and if you are going to smoke any of your harvest... a final flush... even if you haven't flushed at all.. is a MUST....