IMHO 9x7 gallon pots is huge. Really, unless you're using 3000 watts it's a waist of time. I want my plants root bound by the middle of flowering since you don't need anymore roots, you want the energy to go into bud production. More soil doesn't equal more yield, using more than 2 1/2 gallons of soil per 100 watts is an absolute waste of time and money, so if I'm using a 1000 watt, that's a total of 25 gallons of dirt, more than enough to yield the maximum. 25 gallons of dirt can grow 2 lbs of dried product. You're growing in almost 3 times that much and it will result in wispy huge bush's that use all of it's energy on producing branches and leaves, will take 3 months to flower, and if you're not using 3000+ watts will produce a huge amount of nothing. People who've grown out mothers know what I'm talking about. Plus the amount of liquid used to water a 63 gallon grow is enormous and the root system might not be able to transfer the solution out of the giant pots quickly enough resulting in root rot. If you're using 3000+ watts great, but if you're only using 1000 to grow 9 plants with huge veg times in 63 gallons of soil, it's a horrible idea.