Any Perlite experts out there?

[RobbieGanjaSeed]

Ok, I finally worked out the way I'm going forward with this grow, and seeing as I've committed my limited resources already toward it, it is what I will be doing. No turing back now, the goodies are bought.

I want to do something completely different in the long run, but for this grow, I'm going to utilise the odd shape area I have thus-

 

1400mmx800 x about 8 feet tall. !k watts HPS, with a adjusta shade that's almost exactly thelength and width of my grow space.Perfect. I've made c lone/mother set up elsewhere, so it's designated and ready.

 

Apart from the 1200mm sq flood table I scored at the dump for ten bux, last week (when going back ou tthere to se if I could find the 150 watt HPS lights someone here said they could use if they were still around)I actually scored another one (flood table), just bare though., No frame or plumbing. No dmage either but. this one is 1100, x 450. And I scored a "crate" system. You know, one crate ontop of another. Top one loads of slots, which is filled with medium, drippers run down into botom crate, which either flows in a series of other like made pairs to a res. or into a pump in thebottom crate, and back to the drippers.

They charged me 6 bux for the rectagle flood table, and 4 bux for the crates. it was a 25% discount day at the tip, so it worked out about 8 bux for both systems.

 

Still, it doesn't utilise all the space it could in my odd sahped area, so masta grow have a table that's 1200x 650 at a reasonable price, meaning given the plant growing outside the edges, will fill my 1400x 800 wardrobe brilliantly.

 

Instead of flood and drain though (which I'd usuallyuse clay balls I guess), I'm filling it with perlite, and using circe dripers to top feed it, fill the table to the max, with a SOG style grow. I'd use the clay balls and flood and drain as per normal, but the weay I want to take my clones makes me wonder if it'd be stable enought for them. I want to use bare roted clones, and I don't know, but imagine they won't stand well inthe loose flooded clay balls.

 

Instead of the res flooding periodcally, it'll just hold the nutes for the pump to feed the drippers. Clones held tight enough in place by the more stable environemnt 9I hope ) of perlite.

 

Now, I've grown in DWC, Flood and drain, NFT, even simply clay balls with equal parts flock, hand watered. but I've never grown from start to finish in perlite.

 

A person told me if I tried it, the perlite would compact and the plants will stunt, hence he reccomends 25% vermiculite mixed with the perlite. I don't know th bloke raly, and can't say what his real experience withthis medium is, although he could be the ed rosenthal of his disctrict for all i know too. The people at the hydro shop (who have a vested interst in backing this story up to sell me the vermicuculite) said rubbish, no probs at all. Just use rthe perlite, 60 days no compact probs will happen. I however have no idea.

 

The hydro shop people did say however, I'll kill the plants if I run the drippers constantly, which I am embarressed to say is exactly what I had planned to do. I thought the perlite was kinda designed for that treatement, but apparently rot rot, water logging is till aprob, and I suppose that shouldn't be a suprise.

 

they suggested something like 15 minutes drippers on every couple hours.

 

I'm going to take bare root clones in a bubbler, place them directly into the vermiculite and veg a week after they're planted, just to allow to settle, then flower.

 

Anyone got any experience with perlite to warn me what I might come into problems with?

I reckon I should wash it first, last time I used perlite (I had to abandon that grow) it had an amazing amount of compacted dust in the botom.

 

Thanks all.

rob

[bufo marinus]

A person told me if I tried it, the perlite would compact and the plants will stunt, hence he reccomends 25% vermiculite mixed with the perlite. The people at the hydro shop (who have a vested interst in backing this story up to sell me the vermicuculite) said rubbish, no probs at all. Just use rthe perlite, 60 days no compact probs will happen. I however have no idea.

 

The hydro shop people did say however, I'll kill the plants if I run the drippers constantly, which I am embarressed to say is exactly what I had planned to do. I thought the perlite was kinda designed for that treatement, but apparently rot rot, water logging is till aprob, and I suppose that shouldn't be a suprise.

 

they suggested something like 15 minutes drippers on every couple hours.

 

Mate, listen to the hydro shop dudes, they are correct. I would not bother adding vermiculite. The info from your friend is umm, not right.

Perlite works best, like the clay, if it can 'dry out' a little between waterings as it is this action which draws air in and out of the root zone. Plus if the perlite is always wet fungal disease and pests such as sciarid fly can occur.

Wash the perlite if you want, not sure I'd bother if it is drain to waste.

If your just using plain untreated tap water thats cool, just give the table a light flush once a week. Read your runoff if you really want to see what's happening it will tell you if your EC is creeping up/ when you have flushed enough/ and if you have root probs you'll see the pH plummet. Bunnings have good digital timers for less than $20 so you can water in increments of 1 minute which is handy for tuning feeds.

Algae is a bit of an unsightly freebie with the perlite but don't worry too much about it, if you want you can cover the perlite with panda film. That's about all I can think of, good luck with your grow Robbie

[Luke Skywalker]

The perlite probably wouldn't be overwatered if you had drippers running slowly though, it's very well aerated for all it's appearance. Root rot can occur in any media, with warmth, darkness, moisture and spores it's pretty easy to get a water mould brewing in just about anything. Maintenance is the key. Keep a clean system and you'll be fine on that score. Drainage is important though. In a flood and drain table kind of setup I'd perhaps go as far as lining the whole base with some wind-break or coarse shadecloth, and having a long strip of holes drilled into one edge of the table at the basewith a catchment channel directly beneath to drain things off to wherever you want it to go. Have the flood tray on a slope of 1:100 or so, perhaps a little more, and then use the drippers to water periodically. 15mins in the hour sounds okay, but really you should be thinking more in terms of just water until you get a reasonable runoff.... say 20% as a minimum from what you put in, and see how long that takes. Make that a watering perhaps once every hour or two and they'll go nuts. As they grow you'll have to increase watering length or shorten distance between waterings, but you can quickly see if you get runoff after a watering and whether you need to increase it.

 

I'd definitely rinse it out, I find it easiest to just poke some holes in the bottom of the bag with a skewer and then run water from the hose through until it runs relatively clear, then after placing the perlite in the container I'll rinse thouroughly till it's all sorted. God knows why the mate suggested using vermiculite to aerate the mix.... that stuff holds even more moisture and less air than perlite, and has a horrible habit of turning to mush at the bottom of pots.... strange.

 

Get the best perlite you can source. I highly recommend seeing before you buy, and get the coarsest brand you can find. Particle size shouldn't be less than 5mm for best results IMO, and the bigger the better.

 

Perlite rocks, I love the stuff... but IMO best results are in reasonably sized pots. I'd suggest perhaps just using the flood and drain tray as a drainage catchment for some 10L pots, where you can then channel away the drainage from the pots to where you desire....

 

Hope that helps robbie.

[RobbieGanjaSeed]

Thanks Luke, that's great. And hat's to all whp Pmed me.

 

How about thise Phytocell stuff? One shop I went to reckoned people stand in ques to get their hands on it, and they just happened to have bag full right there and then .

 

It was much more expensive than Perlite, but only in the first grow sense, hell it's all cheap in the long run.

 

The fytocell was 55 dollars for 100lires, verses 30 odd for the same weght .. http://fytocell.com.au/

 

I nearly bought it, but without having ee you guys never mention it (is that a double negative, you can se someone "not" something? Gee I say dumb things).. anyway, I hadn't heard of it so was warry.

but what do u reckon mate? The propaganda says it can't be overwatered, and it's bio-degradable.

 

cheers mate. Thanks again.

 

rob

[Dave The Nefarious]

Anyone got any experience with perlite to warn me what I might come into problems with?

never used the stuff so dont listen to me but i know you're supposed to wet perlite/vermiculite before using it because the dust can be harmful or at least very irritating to breathe in

[pipeman]

yeah adding vermiculite to your perlite will INCREASE its density and potential for compaction. Only reason to add vermiculite is if you don't want to water as often and want to increase the water retention capacity of your medium.

 

I'm using the fytocell stuff now for seedlings, only because I got a free sample. Seems OK to me, very similar to perlite.

Edited April 3, 2007 by pipeman

[loylty gets u nothing]

im sure skunk is the 1 that uses straight perlite

i was taught to grow in perlite vermiculite

i almost feel obliged to grow in it again

just as i havent grown in it for so long

 

as for the fytocell rgs

i got a tub of the SHIT in me garage

mixed up as per instructions and sadly ph sits at 2.7

wont be using it again,lucky it was a freeby

all the best

bill

[RobbieGanjaSeed]

Shit! 2.7!! Man I nearly bought a 100 litres of it yesterday, and at the last second thought to myself .."self, wtf are you doing? Your first grow in 2 or 3 years, never done one this way and you want to use a new product you've never heard of?" Lucky self was there huh.

 

Shit man, seriously though, thanks for that warning. All the best with it pipeman, be very interested to know how it all works out for ya.

 

cheers

rob

[buck]

hey rob ive used perlite for a long time now and had no dramas what so ever i dont mix with anything just perlite , you really dont need to mix it with anything for hydro it is very good with water retention and is loose enough for good oxygen levels .

i use a drip feed system on 15 min every 3 hours you will be amazed how much moisture it will hold for a period of time and the non watering intervals help promate root growth as they stretch out to find more nutrients/water , just make sure you use right size pots for good root growth.

 

ps one warning on the stuff is to not breath in the dust it is harmful to your lungs rinse with water before putting in your pots /system as the dust turns to sludge and will block drippers and so on ..

[aussie1]

Hey robbie

I have used perlite for years and also tried other mediums along the way. Perlite is, by

fa, superior IMO. Had a friend who had constant crop failures, just keeling over for

what he thought was no good reason. I nagged him for years to go to perlite, and to stop

feeding them constantly, finally he listened and never has had a failure since.

The odd jagged shape of the perlite makes it almost impossible to compact down

enough to cause any damage, after all that's why we use it, it allows lots of fresh air into the

root zone. The vermiculite is more than likely going to slip into the gaps between the perlite,

and cut off oxygen to the root zone. I would stay away from that guys advice, and I would

not be constantly feeding the plants. They thrive in the same conditions that we do,

and I would not like to be fed constantly?

Good luck with the grow.

aussie

 

P.S It is advisable to rinse the perlite, do as Luke does and poke heaps of holes in the perlite

bag and run hose through til it runs clear. Other wise there will be a wet sludge sitting in the bottom

of your tubs. You should do this in the backyard as my brother ( a plumber) has unblocked many

a drain from sandy perlite dust build up in the low spots of household plumbing.

Edited May 27, 2007 by aussie1