rockwool holding too much water. substitute needed?

[TREE KING]

ive been using 4 inch squared rockwool cubes in flower and overwatering and root rot has been a huge problem, not to mentions fungus gnats. i never want to use it again but at the same time i dont want hydroton either cause its a pain to use. i was also told that since im running h202 i shouldnt use coco cause its organic and the h202 will break it down and cause a mess. does anyone know of a rockwool substitute i can use that also acts as a sponge where if i flood the bottom half inch the whole medium soaks up all the way to the top but at the same time theres more air than rockwool available to the roots? fytocell would of been perfect but i cant find it in the u.s right now. this is for ebb n flow thanks

 

[growshopfrank]

before you abandon rockwool have you tried placing the blocks on a grid to promote drainage grodan makes a product called gro-smart tray they work good but are expensive another option would be egg crate diffuser used for florescent fixtures
FWIW i cant recommended sure to grow medium as it is expensive to use and dries very rapidly without any performance benefits over rockwool imho

 

[MIway]

hempy... vermiculite & perlite. u can adjust the blend & size to get pretty much anything you could want for a dry/wet ratio.

 

[TREE KING]

hempy... vermiculite & perlite. u can adjust the blend & size to get pretty much anything you could want for a dry/wet ratio.

wow so your sayin if i mix vermiculite & perlite together it will act similar to rockwool and soak up like a sponge? i want to be able to water my plants 3-4 times a day instead of once a day with rockwool, what % of each do you recommend?

 

[FreezerBoy]

another option would be egg crate diffuser used for florescent fixtures

ROTFLMAO!

Tried that once. Couldn't find the egg crate after harvest. It was so overgrown with roots, it looked like someone put a horse hair door mat down there.

It definitely works. Whether it's worth the cost of throwing it out or the effort of reclaiming it... only TK can say.

 

[Maj.Cottonmouth]

If you want to water that much and do a hempy style you will want a very high percentage of perlite because it drains fast, vermiculite holds water. I ran 3 parts perlite to 1 part vermiculite and I watered once every two to three days. You might want to try one in straight perlite and see if it holds enough water to allow the 3-4 times a day waterings without drying out.

 

[TREE KING]

If you want to water that much and do a hempy style you will want a very high percentage of perlite because it drains fast, vermiculite holds water. I ran 3 parts perlite to 1 part vermiculite and I watered once every two to three days. You might want to try one in straight perlite and see if it holds enough water to allow the 3-4 times a day waterings without drying out.

the only thing is people keep telling me that perlite acts similar to hydroton and doesnt soak up similar to a sponge/fytocell/rockwool. can you confirm this?

 

[MIway]

the only thing is people keep telling me that perlite acts similar to hydroton and doesnt soak up similar to a sponge/fytocell/rockwool. can you confirm this?

you can even use hempy with a nylon rope for a wick & passively water em... it'l suck up the moisture. great stuff, but i like to topfeed d2w... just easy... basic. but like MC is getting at... just gotta find the magic balance for your room conditions & the mix. use the fine grade perlite either way, with these type of mixes, just works better imo.

 

[TREE KING]

you can even use hempy with a nylon rope for a wick & passively water em... it'l suck up the moisture. great stuff, but i like to topfeed d2w... just easy... basic. but like MC is getting at... just gotta find the magic balance for your room conditions & the mix. use the fine grade perlite either way, with these type of mixes, just works better imo.

yeah i just dont have the time to try to find the right balance cause this is a once or twice time thing then im switching to aeroponics permanently. are you talkin about just dumping them in a pot with no plant in it and then seeing how quick it dries out in a few hours or something like that? i was hoping one of you guys could recommend a % of each.

 

[Maj.Cottonmouth]

That is correct, I do not believe there is any capillary action with the perlite so it will not wick up water but if you are top feeding 3 to 4 times a day this is what you want so that it drains away and dries out some before the next watering.

 

[Maj.Cottonmouth]

I know you can grow in straight perlite, check out the hempy bucket thread to see what specific ratios people used.

http://www.icmag.com/ic/showthread.php?t=98419&highlight=hempy

 

[wisco61]

i was also told that since im running h202 i shouldnt use coco cause its organic and the h202 will break it down and cause a mess.

This is bad info. You could use coco.

 

[TREE KING]

This is bad info. You could use coco.

hmmmmm interesting. what about these cocogro cubes
http://www.growsmarthydroponics.com/Boss-6In-Cocogro-Cube-_p_14441.html
i can water those more than rockwool right? i dont really know that much about coco but is there some 4 inch squared cubes of them similar to rockwool cubes? it would be nice to not have to buy pots. just so you know il be using advanced nutrients sensi 2 part, is that ok?

 

[resinryder]

If your 4 inch cube is holding too much water and you're getting root rot you are flooding too long. Been using the 6 inch cubes for years, tho lately more coco coir with perlite added in 2 gallon smartpots, and the only time I ever had the problems you mentioned was due to over watering. And fungus gnats will get into any medium you use. I still don't understand the need people have to use H2O2 either. If you need it you're doing something wrong.
I have a friend that uses cotton in the small net pots for his aero system. He likes it but it starts looking nasty after a little while. He continually has problems with the system too. Ph swings, water temp problems, ppm swings. I'd rather do e&f with over sized reservoirs and auto grow the girls instead of worrying about my system preforming correctly on a daily basis.
Just my 2 cent...Good luck!

 

[TREE KING]

If your 4 inch cube is holding too much water and you're getting root rot you are flooding too long. Been using the 6 inch cubes for years, tho lately more coco coir with perlite added in 2 gallon smartpots, and the only time I ever had the problems you mentioned was due to over watering. And fungus gnats will get into any medium you use. I still don't understand the need people have to use H2O2 either. If you need it you're doing something wrong.
I have a friend that uses cotton in the small net pots for his aero system. He likes it but it starts looking nasty after a little while. He continually has problems with the system too. Ph swings, water temp problems, ppm swings. I'd rather do e&f with over sized reservoirs and auto grow the girls instead of worrying about my system preforming correctly on a daily basis.
Just my 2 cent...Good luck!

all i know is if i can water a 4" cube and its still heavy and soaked 5 days later than i dont consider that a good thing and another negative ive noticed is if i dont water the cubes for days then the plant barely grows anymore after a couple days after watering. then i gotta sit there and watch the plant not grow for a few more days while i let the cube dry out. it seems like the plant needs new nutes but theres too much water in there to water it again. in my opinion i think with an ebb n flow system the water needs to be flowing to the roots more often

 

[resinryder]

Damn bro I've never heard of them staying that wet for that long.
They are supposed to hold some moisture but not stay "wet" for that long. I water mine every 4 hours for as long as it takes to either flood half way up the block or up to the over flow, which ever come first. The for another 1 minute after that. Tis is usually 5 minutes on my 2 x 4 or 7 minutes on my 4 x 4(which uses a bigger pump).
What happens is every time it floods it feeds the plant and exchanges the air. Both are needed for plant growth. And you're right-If they just sit there without being flooded they don't grow.
Depending on plant size, I have to flood every 4 hours. If the plants are big, I grow trees, they will dry the block out in a 6 hour time frame. That's why I use the 4 hour cycle.
They should stay a bit wet, not soaked, between floods. If they dry out too much the smaller roots in the cube die off.
A few questions to try and figure out what's going on.
What size table?
How long do you flood?
How tall are the plants or how far into the bloom cycle are you?
What are the temps and humidity in the room?
What is the nutrient ph?

 

[TREE KING]

Damn bro I've never heard of them staying that wet for that long.
They are supposed to hold some moisture but not stay "wet" for that long. I water mine every 4 hours for as long as it takes to either flood half way up the block or up to the over flow, which ever come first. The for another 1 minute after that. Tis is usually 5 minutes on my 2 x 4 or 7 minutes on my 4 x 4(which uses a bigger pump).
What happens is every time it floods it feeds the plant and exchanges the air. Both are needed for plant growth. And you're right-If they just sit there without being flooded they don't grow.
Depending on plant size, I have to flood every 4 hours. If the plants are big, I grow trees, they will dry the block out in a 6 hour time frame. That's why I use the 4 hour cycle.
They should stay a bit wet, not soaked, between floods. If they dry out too much the smaller roots in the cube die off.
A few questions to try and figure out what's going on.
What size table?
How long do you flood?
How tall are the plants or how far into the bloom cycle are you?
What are the temps and humidity in the room?
What is the nutrient ph?

i do sea of green with no veg but this crop since it was from seed a had a few weeks veg but plants didnt grow that much because of the overwatering. you should see some of my roots right now lol. black sludge goo all over the place. discusting! the most i ever watered them from day 1 was 2 times a day. i guarentee you if you flooded a 4 inch rockwool cube with a brand new clone in it, a week later if you squeezed it there would be a ton of water pouring out of it. humidity was around 45-50, id flood for 15 minutes and plants right now are around 2 1/2 to 3 ft tall but there pretty much all done. i had a 4 x 8 tray and a 4 x 4 tray ph 5.6 drifting up to 6.1 plus i used a water chiller. i never used h202 this crop but you can bet from now on im using it every 3 days for good. things might of turned out differently if i used it

 

[resinryder]

Everything sounds good except for the flood time. Just too much water. 15 minutes on then 10 minutes or so to drain. But that's my opinion.
Everything else looks like it should.
The buds the plants have put on should be pulling all that excess water out of the cube.
The pump isn't coming on during the dark period is it?
Next time if you have root rot problems, use SM90 at full strength. It'll stop it. But you don't want to use it too far into bloom because it can be tasted in the final product.
Def got me stumped. Wish I could help. This is just odd.

 

[TREE KING]

Everything sounds good except for the flood time. Just too much water. 15 minutes on then 10 minutes or so to drain. But that's my opinion.
Everything else looks like it should.
The buds the plants have put on should be pulling all that excess water out of the cube.
The pump isn't coming on during the dark period is it?
Next time if you have root rot problems, use SM90 at full strength. It'll stop it. But you don't want to use it too far into bloom because it can be tasted in the final product.
Def got me stumped. Wish I could help. This is just odd.

pythium is the devil thats all i know lol. i cant wait to switch to aero in a couple months then there will never be water sitting it a medium for a long period of time

 

[SKUNK420]

maybe you should give Pargro quick drain rockwool a try first.
http://www.grodan101.com/products/pargro-stonewool