the bigger the root, the bigger the fruit
I wouldn't flower with anything smaller than 3 gallon
rule of thumb is 1 gal for every month your plant is alive i.e. 3 months = 3 gal. pot
No the rule of thumb is 1 gallon for every foot. Not everyone uses cfl's
What about the SOG method? Clones put directly in flower can grow a meeter tall and still bud great in 6inch pots.