I don't know much but I would lower your lights to no more than 18", also, as they get bigger they will drink up more water so, don't let them run dry. One last thing, I don't know what your plans are but I think 7 plants are too many for a 36X36 tent, My tent is 4X4 I gave one plant away, I should have sold it 7 weeks old but I didn't, to reduce my count to 5 I am moving one around my backyard following the Sun. I could grow 6 but I would have to give up on keeping them a part completely, even with netting. In my 1st time grower's opinion the amount of greenery is more important than the size of the pot. I use 5gal. bags because I want the roots yo have ample room. I think Puglover1 is right about about runoff as well.