Not sure what your describing there mate but it's not how a flood and drain table works. The table has a permanently open drain hole with a small diameter and an overflow hole set to the height you want to flood. The water is fed at the opposite end of the table and gives a constant flow of feed accros the roots. Whilst the table is filling, it is also draining at the same time but at a much lesser rate than the incoming water, voila..... constant flowing oxygen and nutrient rich supply. How do you drain your table after flood? OP.... I don't think that would work, the medium will float giving you no end of problems. I am new to this and considered the same, u can't really swerve the pots. I would not advise on rockwool, it retains too much fluid and you would only need to flood every couple of days, any more would give you problems. Hydroton give best results by a mile.
I would use hydroton, heard the same about it being the best, but I could also even step it up to pea gravel or something similar, something with enough space for roots yet dense enough not to float.
that n thats lot of medium to pay for
In the long run of things, it wouldn't be THAT much more expensive than growing in pots. I have to buy a big enough bag to fill my pots and I'll have leftover regardless, plus I could group the plants closer together, and with more horizontal space to grow the medium would not have to be quite as deep. I would need more, but I don't think that much more.
what you describe is more of a drip system then a flood and drain. typically the fill tube comes in at the bottom of the flood table and the drain is set for the flood depth so water will not rise past this point even if the pump doesn't turn off for whatever reason. your design would overflow if the timer stopped working and the pump didn't stop. You always want your drain tube to be larger than your full tube. You can use your medium directly in the flood table but I prefer pots so plants can be rotated or pulled individually for inspections if needed.
I guess if I had the inflow at the top it could technically be considered a drip system, but it's not constant and it's one giant pot instead of flowing into 3 separate ones. As MrMeanGreen said I would include a large diameter overflow pipe just in case something malfunctioned and the pump didnt shut off. I'm planning on a ScrOG, so the ability to move plants doesn't hold much interest for me, but I get your point. The only reason I've thought about this is an article I read about plant behavior recently that stated if two different kinds of plants were planted in one pot they would fight each other for nutrients and grow as tall and as quick as they could, resulting in harm for both plants. However, with two plants of the same species they would grow in harmony with each other, sharing nutrients and space resulting in the best possible outcome for all plants. I guess the only way to really know would be to try it out, I might end up doing it this upcoming year just to see what happens. I'd run a couple cycles to get my process down straight, get a benchmark weight, then try the new setup and see what happens
