Question about rockwool
- Thread starter Spliffer1
- Start date
stalebiscuit
Well-Known Member
you want to fill an entire 3 gallon pot with only rockwool? or you want a piece of rockwool the size of a 3 gallon pot; cause either way thats alot of inert material
fragileassassin
Well-Known Member
Probably the worst medium out there.
Do literally anything else.
Do literally anything else.
Spliffer1
Well-Known Member
No, I'm wondering if I can grow the same size plant in say a 6x6x6 cube, as I can in a 3 gal soil pot. Trying to get an idea of how large a cube, or mass I need to grow some fair size plants, like I normally grow in 3 gal of soil
I'm making the change from soil to hydro. I'm in the learning curve lol
Spliffer1
Well-Known Member
Why so?
I am new to hydro, so this is mostly pretty new. I've done a couple bubble buckets with hydroton, a few yrs ago with some success. But I'm trying to think on a larger scale
Greens2000
Active Member
Disagree
Animatey
Active Member
You can grow pretty big plants in a 6x6x6.
I've had them a little more than 4 feet. Any bigger than that and you might wanna stack the 6x6x6 on a slab, or start in a 4x4x4 and then stack that on a 6x6x6 or a slab.
These were 6x6x6, all plants at least 3 feet tall (8 plants in a 2.5x2.5 foot tent). You can see the cube size clearly in the second picture:
I've had them a little more than 4 feet. Any bigger than that and you might wanna stack the 6x6x6 on a slab, or start in a 4x4x4 and then stack that on a 6x6x6 or a slab.
These were 6x6x6, all plants at least 3 feet tall (8 plants in a 2.5x2.5 foot tent). You can see the cube size clearly in the second picture:
Spliffer1
Well-Known Member
NICE!!
Thanks for your input! That is exactly what I'm wanting to find out.
A couple more questions, if I may-
At that stage in flower, how often do you have to water? It appears you have an ebb/flow setup, which I have no experience with. But the concept is easy to follow. I'll be using a re-circulatory drip system
And, where did you find those clip on fans? Those look like the cat's meow for the application you're using them.
Thanks Animatey
Animatey
Active Member
With flooding I actually only had to flood once per day even in flower. Using drippers is a little different. Flooding really soaks the blocks.
With top feed they don't get as saturated because you start getting run off before the block is completely soaked even if you are dripping really slowly.
Grodan has a pdf about how to water the blocks with drippers which I'll attach here. They also have some additional tips for hugos (6x6x6) which I'll attach as well.
The clip fans are genesis brand from Amazon. They have worked ok so far.
I just started a few plants using top feed and they are a little stalled. The hugo needs to dry to 50% before being watered. I tried to water it more frequently and the plants got lazy.
These are about 3-5 days of progress behind where my plants normally are:
I use a water proof kitchen scale to weigh them. In veg I'd wait until the blocks get to 50% of their max weight to water. Once the roots fill the block you can water like the pdfs say. The hugo pdf says you can water the hugo when it's 70% it's original weight, but I wouldn't do that until roots have had time to fill the block some.
This is just my .02$, I'm not the most experienced rockwool grower, but hopefully this helps.
Spliffer1
Well-Known Member
Some good information there!
Thanks!
Dontjudgeme
Well-Known Member
I hate rockwool cubes, I don’t know why, but my clones root waaaaay faster with jiffy pellets. I mean I still get roots using rockwool, just takes longer.
Spliffer1
Well-Known Member
What little I have used it, that's been my experience, as well. Been watching a lot of youtube about using rockwool, and it's impressive what some are doing with it.
I've been using soil for the last ump-teen years and want to switch to hydro. Still studying mediums, methods, etc., to see what will work best in my garden. I've done a few dwc bubble bucket over the years, and I'm sure I'll get a few of those going along with the rockwool until I get the hang of it. I don't really want to put all my eggs in one basket
kernelforbin
Member
Most rockwool cubes have a native pH in the high 7's, so they must be soaked in pH balanced water before using. This is almost impossible to correct. Soak a cube for 48 hours, squeeze the water out of the cube, test it, and you'll see it's still high. This makes it a difficult, unnatural environment for clones and seedlings.
This is in addition to rockwool being a man-made material with both environmental and personal health risks. For the same reason care must be exercised with working with insulation, rockwool can get into your eyes, mouth, and in your skin because it's a tiny fibrous material that is always flaking.
You can start a seed in a bubble bucket by just putting the seed on the hydroton and filling the water level so the bubbles pop on the underside of it. For clones nothing beats an aero/hydroponic cloner. No need to over complicate things.
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Major Blazer
Well-Known Member
The residual lime in rockwool dissolves in water - a 30m soak is all that you need to fix any potential pH issues.
@Spliffer1 if you used to soil, perhaps try something like grodan gro-cubes. I used to utilize a 80/20 ratio of gro-cubes and hydroton in fabric pots, drip fed; worked really really well. Used the same thing doing flood and drain too. Rockwool is an awesome medium for me, I use it all the time in various steps of grow.
@Spliffer1 if you used to soil, perhaps try something like grodan gro-cubes. I used to utilize a 80/20 ratio of gro-cubes and hydroton in fabric pots, drip fed; worked really really well. Used the same thing doing flood and drain too. Rockwool is an awesome medium for me, I use it all the time in various steps of grow.
Growoolit
Well-Known Member
FYI
- Always pre-soak the rockwool in pH 5.5, not plain water
-Never, ever squeeze the cubes. Structure damage cannot be rectified. New cube required.
- Wear gloves when working with rockwool. Probably a nuisance-dust mask too.
I grow in loose rockwool and can't get enough of it.
Animatey
Active Member
The caps and clips are really nice. The clips come off fairly easy so you can move plants around. The caps do a good job of preventing algae and help spread water evenly if you are watering by hand or without pressure compensation.