Help Irritating Rockwool

[damien50]

So I have this Rockwool medium by a company called gelato and I used it on my last grow with a less than adequate top drip system. I think the plants ended up root bound with constant yellowing leaves like a nitrogen deficiency. I switched from coco and attempted to water the same way and got less of a yield and quality than I hoped for.

How much or often should Rockwool be irrigated?

What times during lights on/off?

Is it over watering if I get algae growth?

This is like a spun wool sort of and can go into pots.

Should I be aiming for runoff every irrigation?

 

[aridbud]

We used to use rock wool and those lava marbles together....created aeration.

Algae is pretty common on surface of cubes...black plastic to prevent light. Algae will grow anywhere it finds these three things- water, nutrients, and light. Since the whole hydroponic system is filled with constantly re-circulating nutrient solution, the only one of these three ingredients you are able to remove from the equation is light. Any place in the system where nutrient solution exists, you need to exclude light as much as possible. Keep your nutrient solution in a light-proof reservoir (with a lid). Make sure there is not light exposure where the nutrient solution enters the system and where it returns to the reservoir. For drip system, you can cover the tops of your planting medium with pieces of black plastic, with the drip emitters run underneath the plastic. Keeping the light off the rockwool will prevent algae growth on the rockwool.

You can also add a small amount of Hydrogen Peroxide into the nutrient reservoir. Once you begin killing back the algae, you MAY want to change the nutrient solution more frequently (as it will become saturated with bits of dead algae). Be sure to read my page on using Hydrogen Peroxide if you decide to go this route, as the Peroxide can wipe out your entire garden just as quickly as pythium or fusarium if you use it improperly.

 

[f-e]

It sounds like your growing in roof insulation.

Our rockwool keeps it's shape. More importantly, it keeps the space between strands. Strands orientated to drain.

Roof insulation for loose fill won't be orientated to drain, and will compact as the plants grow. It would be a sodden mass.

Sheet rockwool insulation looks more like ours, but doesn't have the same capillary action. Voids within it channel the water unevenly.

Gelato, from the makers of iRockwool.


P.S I hope you wore a respirator handling that stuff

 

[damien50]

Sorry the company is called Growpito.

It doesn't maintain shape. The owner gave me a bag to try but suggested flood and drain and has never used top feeding so he had no suggestions. I figured from everything I've read to water small but frequently.

 

[damien50]

There are some pics of the medium

 

[aridbud]

Sorry the company is called Growpito.

It doesn't maintain shape. The owner gave me a bag to try but suggested flood and drain and has never used top feeding so he had no suggestions. I figured from everything I've read to water small but frequently.

Read their website. Supposedly the fellow developing Growpito....if he cannot attest to top watering....he's not much of a horticulturist....even though it says he has 30 yrs experience. Hmmmm.

 

[soil margin]

Christ damien that does look more like roof insulation than rockwool. I've only done 2-3 grows with rockwool but it always came in cubes and kept it's shape as others have said. Never had problems with overwatering or algae growth. Good luck though, I'll definitely be impressed if you can grow some dank in that medium.

 

[damien50]

Read their website. Supposedly the fellow developing Growpito....if he cannot attest to top watering....he's not much of a horticulturist....even though it says he has 30 yrs experience. Hmmmm.

Yeah I know right. He thinks flood and drain is the Holy grain of water/nutrient preservation and considers top feeding wasteful. I'm trying it because it's reusable mostly and I'm going to use it in a vertical vegetable garden.

 

[Medfinder]

That pic tells the story. Does look like insulation.

And roof insulation has much different fibers. Roof insulation fibers irritate skin and lungs..keep any fiber moist so it doesn't go air Bourne... You have heard of mesothleoma right...fiber masses in the lung tissue.

 

[damien50]

Christ damien that does look more like roof insulation than rockwool. I've only done 2-3 grows with rockwool but it always came in cubes and kept it's shape as others have said. Never had problems with overwatering or algae growth. Good luck though, I'll definitely be impressed if you can grow some dank in that medium.

I finished a grow last month of some 00 seeds auto kush/California kush and I pretty much end up with 8oz from 4 plants because they all ended up root bound in 1 gallon pots. I don't think I over watered necessarily but I think I should treat it similar to Rockwool and do frequent/short watering cycles during lights on rather than keeping it 75% or so saturated all the time.

I'm going to set up a top feed with tee'd 1/4 soaker lines and do short 1 minute cycles while I control the flow with individual ball valves in 5 gallon pots with Malawi from Ace.

 

[damien50]

That pic tells the story. Does look like insulation.

And roof insulation has much different fibers. Roof insulation fibers irritate skin and lungs..keep any fiber moist so it doesn't go air Bourne... You have heard of mesothleoma right...fiber masses in the lung tissue.

I keep it in a cooler soaking in enzymes and .5 ec water. I'm pretty sure it's not insulation, it doesn't irritate the skin, and it doesn't really get airborne.

 

[aridbud]

Yeah I know right. He thinks flood and drain is the Holy grain of water/nutrient preservation and considers top feeding wasteful. I'm trying it because it's reusable mostly and I'm going to use it in a vertical vegetable garden.

Hope it works out.

Recall Grodan had loose fill years ago....it's was waaay too heavy, hence into marble lava & perlite. Prefer organic soil (no rockwool particulate)....you can leave it for days...no monitoring until bloom stage (speaking for autoflowers).

Once you can get it copacetic, you'll do fine. Too, you can mix in perlite....it won't dry out medium...it just helps add medium's "fluff" for aeration and root growth.

 

[pumpkinpie eyes]

I finished a grow last month of some 00 seeds auto kush/California kush and I pretty much end up with 8oz from 4 plants because they all ended up root bound in 1 gallon pots. I don't think I over watered necessarily but I think I should treat it similar to Rockwool and do frequent/short watering cycles during lights on rather than keeping it 75% or so saturated all the time.

I'm going to set up a top feed with tee'd 1/4 soaker lines and do short 1 minute cycles while I control the flow with individual ball valves in 5 gallon pots with Malawi from Ace.

way to grow

 

[damien50]

Hope it works out.

Recall Grodan had loose fill years ago....it's was waaay too heavy, hence into marble lava & perlite. Prefer organic soil (no rockwool particulate)....you can leave it for days...no monitoring until bloom stage (speaking for autoflowers).

Once you can get it copacetic, you'll do fine. Too, you can mix in perlite....it won't dry out medium...it just helps add medium's "fluff" for aeration and root growth.

Thanks. I can't say that it actually ever compacted. This stuff is super light, retains water well and my roots had amazing, in my opinion, growth despite mistakes.

I tried soil on my first grow with bag seed and ended up with mites and fungus gnats. I did coco for two grows but this was free and I wanted to compare it to coco. I think it just needs to be treated like Rockwool and it will, hopefully, be fine lol. I'm done growing autos and going to photos so I can monster crop for a perpetual grow.