Rockwool and Coco Slabs

since1991

Well-Known Member
This isnt so much advanced as it is probably unheard of here because I know slab growing is not very popular in the States (for cannabis at least - produce greenhouses are way ahead of the ball) ..whether its rw or coir. I dont know why either. Low clearance...more root space..easy as pie...and more. Its what the big greenhouses use. Cant move individual plants is the only negative...and i dont do that anyways. But if any one here messes with non recovery slabs do you know if there is a coco slab (bag , sleeve, ) that fits those black Dutch "Libra" trays? If i could source quLity coir in that slab size i would be all set ( the rw slabs i use to use were standard 4" tall 6" wide 36" long - the tray themselves are 6" wide x 40" long ). I use to run rockwool slabs back in the day and i have a shit ton of Libra Trays just sitting in a corner of my basement and i could o
put them back to use.
 
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dadio161

Well-Known Member
Rockwool does come in a 6" x 6" x 6" block . That's what I use and I can move my plants around as needed . Lots of room for the roots . With a 36" tray , you can probably fit three in each one .
 

since1991

Well-Known Member
Yeah ive used them. Looking for coco slabs that fit the libra trays is tough here in America. No one grows in slabs anymore....rockwool. And no one ever grows in coco slabs at all. Europe thats all they use seems like.
 
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since1991

Well-Known Member
Main reason for slabs i like is i got the trays just sitting in my basement. A bunch. Havent used in years. More room for roots in slabs....and the most important....with my 6.5 foot tall basement every inch i can gain in height clearance is valuable real estate. Especially with a bunch of 600 watt Gavita double ended fixtures. Iam using saucers with 2 gallon root pots now. And have to manually shop vac run off. Tables with drain fittings....i lose vertical clearances that i cant afford. With slabs all nice and low...in them dutch trays....would be perfect.
 
I was actually wondering the same thing as I was going through this forum. It seems this day everyone is either running DWC or Coco. I get the R/DWC because it's awesome and yields great. I have also seen some really experienced growers do great with Coco, but it seems like Coco is more like soil and only the best growers can yield well compared to Hydroton/DWC. I've seen less experienced growers run side by side coco and DWC and the coco gets blown away. I've also seen DWC side by side with Rockwool and the yields were roughly the same. I realize there are a lot of other factors that need to be dialed in, and it also has to do with the experience of the grower with the chosen medium, it just seems like Rockwool is pretty simple for the beginner and comparable to DWC in terms of yield. I don't understand why I don't see more people growing in Rockwool cubes or slabs. It's an amazing medium. And slabs make a lot of space (in a compact area) for vigorous roots.
 

since1991

Well-Known Member
I was actually wondering the same thing as I was going through this forum. It seems this day everyone is either running DWC or Coco. I get the R/DWC because it's awesome and yields great. I have also seen some really experienced growers do great with Coco, but it seems like Coco is more like soil and only the best growers can yield well compared to Hydroton/DWC. I've seen less experienced growers run side by side coco and DWC and the coco gets blown away. I've also seen DWC side by side with Rockwool and the yields were roughly the same. I realize there are a lot of other factors that need to be dialed in, and it also has to do with the experience of the grower with the chosen medium, it just seems like Rockwool is pretty simple for the beginner and comparable to DWC in terms of yield. I don't understand why I don't see more people growing in Rockwool cubes or slabs. It's an amazing medium. And slabs make a lot of space (in a compact area) for vigorous roots.
With DWC or RDWC the yields and speed is awesome. But the buffer or margin of forgiveness is not there compared to coco coir ir rockwool drain to waste grows. Thats why big ag greenhouses do not use dwc excpet maybe raft systems for lettuce production. If something goes wrong in DWC grows...its downhill....fast. The yields are not that much lower with a medium based system and your forgiveness buffer is much much greater.
 

Aeroknow

Well-Known Member
I grow mainly in big pots of dirt/coco/soil lately.
But I'm always still getting my hydro on. Here's a small crop I just spread out and flipped the switch yesterday.
image.jpeg
image.jpeg
My goto is 1gal mesh bottom pots with coco/perlite. Basket drip stakes.
I mess with all kinds of shit and it's all good. I got 3"ers on hugos i'm about to take down here soon. Killed it with that too:-D

@since1991
What are you looking for in a coco slab, that rockwool won't do for you? Just curious.
 

Chillin chillin

Well-Known Member
I grow mainly in big pots of dirt/coco/soil lately.
But I'm always still getting my hydro on. Here's a small crop I just spread out and flipped the switch yesterday.
View attachment 3651061
View attachment 3651060
My goto is 1gal mesh bottom pots with coco/perlite. Basket drip stakes.
I mess with all kinds of shit and it's all good. I got 3"ers on hugos i'm about to take down here soon. Killed it with that too:-D

@since1991
What are you looking for in a coco slab, that rockwool won't do for you? Just curious.
Do you see a significant difference in yield w the slabs?
 

Aeroknow

Well-Known Member
Do you see a significant difference in yield w the slabs?
Not really. I just get bored real easily, so i decided to rock the slabs this time :-D
I might do it again next time, but like I had said earlier, 1gal pots full coco+perlite is my goto setup when running lots of plants per light.
 

Aeroknow

Well-Known Member
How often do you water w slabs, how much per watering?
I water 10x a day 2 min each time w 4gph dripers. Gets fat yields this way
I water until plenty run-off has been acheived.
Now that they are in flower, i'm only 1X, right when lights come on. I'll most likely end up at 2X in about a week or so. Prob, won't have to go up to 3X's with these slabs. I went with a bigger slab then I've ever used before. They're plenty big for the size plants these are, which is 12 plants per 4x4.
My 3"ers ontop of hugos, I end up at 3x's a light cycle. Same with 1g pots of coco, 3 times. But those setups are 16 plants per 4x4. Looks like you are growing trees in your hugos, just a little different:-D
 
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since1991

Well-Known Member
I grow mainly in big pots of dirt/coco/soil lately.
But I'm always still getting my hydro on. Here's a small crop I just spread out and flipped the switch yesterday.
View attachment 3651061
View attachment 3651060
My goto is 1gal mesh bottom pots with coco/perlite. Basket drip stakes.
I mess with all kinds of shit and it's all good. I got 3"ers on hugos i'm about to take down here soon. Killed it with that too:-D

@since1991
What are you looking for in a coco slab, that rockwool won't do for you? Just curious.
Nice. Non recovery? What i like with coir is ease of use. No pH dicking around. And disposal and/or reuse. I use to run wool slabs. They were great. No difference than coir if the truth be known as far as growth quality and yield. But they were a pia to get rid of. Back in the day i needed but never had them roller dealys that Grodan suggested to wring them wet fukers out with. Coir i can reuse a few times and then chuck it in my vevgie garden. Looks just like "dirt". Nice slab set up though. Not alot of cats run slabs anymore.
 

since1991

Well-Known Member
I should go back to rockwool slabs. Coir slabs are damn near impossible to source here in the u.s.a. and i like the clearance height.
 

since1991

Well-Known Member
I grow mainly in big pots of dirt/coco/soil lately.
But I'm always still getting my hydro on. Here's a small crop I just spread out and flipped the switch yesterday.
View attachment 3651061
View attachment 3651060
My goto is 1gal mesh bottom pots with coco/perlite. Basket drip stakes.
I mess with all kinds of shit and it's all good. I got 3"ers on hugos i'm about to take down here soon. Killed it with that too:-D

@since1991
What are you looking for in a coco slab, that rockwool won't do for you? Just curious.
You gonna slap up a net trellis with that run?
 

Aeroknow

Well-Known Member
You gonna slap up a net trellis with that run?
Absolutely!
Nice. Non recovery? What i like with coir is ease of use. No pH dicking around. And disposal and/or reuse. I use to run wool slabs. They were great. No difference than coir if the truth be known as far as growth quality and yield. But they were a pia to get rid of. Back in the day i needed but never had them roller dealys that Grodan suggested to wring them wet fukers out with. Coir i can reuse a few times and then chuck it in my vevgie garden. Looks just like "dirt". Nice slab set up though. Not alot of cats run slabs anymore.
Yeah, it's just run to waste. I would totally prefer it be a recirculating, as that's whats killer over running coco in pots, but the trays are only about 8" off the ground. The ceiling height is only 8' and i'm rockin DE's in there :-D
 
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