hey smoke, I use a 2x4 ebb and flow with six plants , I spaced them at 12-13'' on center, my clones are in 3x3x4 grodan rockwool. all I do is take the plastic off the cubes and stick them straight in the rocks..I get really good root growth,by the end of the grow the root will take up the tray...one big root mass..I've never had a problem with the plants falling over, just when they are budding and getting heavy,then I tie them up. I can have only 6 in that size tray, so they don't crowd...what I like doing is bending them over, I take the tops and bend them to each corner and the middle ones I bend to the sides..if you do it right you should have a mini sog. I water 4 times a day for 3-4 min..it takes that long to fill the tank up to about the top of the cubes, then it drains out..the whole cycle takes 13 mins..when I go 12/12 I water 3 times at about 5-6min by now the roots are getting thick and it takes a little longer..you'll have to work on the water..for the nutes I use nothing but general hydro, flora plus, and diamond necter...I've never had any problems...one thing I learned is take ph readings from your cubes as well as your res ...sometimes the ph in the cubes will drift toward the lower ph..so I just raise the ph in my res and it equals out...change your nutes every 4-5 days..I like keeping them fresh...good luck with your grow