im in 7 gal fabric pots and i water 1 gal once a week. plants are all 3-5 feet tall depending on strain. and 2 weeks into flower.
I use 5 gallon fabric pots, and completely drench and leave 2" of water in drip-base....every third-fourth day. And it is about 1.5 gallons per plant. I use Roots Organic Coco.