ok guys, I'm experienced using these kiddie pools, I had 7 or 8 of em on my big 40 grow last year. My first year seriously growing, I had a Jack Herer x TrainWreck that was in a 30 gallon bag, and by mid July I was watering twice a day just to keep it from crashing. I went to Wal- Mart and got a 6' kiddie pool and 6 bags of soil, and transplanted it in that, and that went on to yield 3 pounds of cured dried buds. I was sold and have been using them on and off since. Pot plants roots really like to go out more than down, especially a clone, and the wider the root system, the wider the plant. Sedds are different, they do prefer to go down with a tapo root, but they really don't go that deep ,and they will turn and go out when they hit the bottom. I would advise a smart pot 100 gallon at least for a seedling, but for clones, those pools work great. My big grow last year, the rows were 10' wide, but only 2' deep, and you see they loved it. Deep and skinny holes make tall, skinny plants. Wide shallow holes make wide bushy plants that always yield better than the tall skinny ones.