Pot size

Depends on how big you want the plants, and how nutritious the soil is. - If you know what you're doing with fertilizers, even a 1 liter pot can work out pretty good. Tho, iif you aren't all that knowledgable on fertz, you should opt for bigger pots. 8 - 11 liter will work fine for autos, and depending on nutrition values of soil, you likely won't "need" to feed until the very end of the grow. - If you want some big photos filling your tent out as much as possible, you could use 20 liter pots.. Tho, might be a good idea to start smaller, and then repot later on as they get bigger. ^You won't fill the tent unless you top and/or do LST tho. They'll just grow tall.