Autos are only gonna be with you for 2-3 months so at a gallon per month, use 2-2.5 gallon pots, now you need a cfl array that will cover that 5 x 2.5 gallon pots, budget on 2 cfl per plant at full grown 3 is better, design and build your cfl array, stick to 2700k or warm red light color as you want autos to stretch in the first place, top on the second lateral for another half oz, keep a fan and a temp gauge in there, and read up shit loads ...good luck