Need Advice on light/ fan setup

I already have a 600 Watt Hps Cooltube and digital ballast. Now how many 2.5 gallon containers can I fit underneath it to get optimium light to plants, also what kind and size fan would work to cool the light off? I'm going to grow in hempy buckets, how much yield can I expect to get? I know alot depends on that, but estimate amount is what I'm looking for. Going with the strain Whiteberry.

ive got a 450 cfm fan (6 inch) cooling a 600 + 400 and temps stay perfect, ive also set one up for a friend and they are using a tt 125 fan rated at 220 cfm and it keeps the temps perfect also, you want at least 200 cfm to cool the 600, this depends on the intake air though. the 600 covers a 4x4 area and i can fit 6 x 3 gallon buckets under with the plants finishing at around the 3 foot mark. as for yield it depends on alot of things but with the 600 i wouldn't be happy with anything less than 10-12 oz.