How did you come up with 70-gallons? Even if you only fill your buckets with 10-gallons each, that still amounts to 90-gallons. I would go with at least 1000gph. Are you planning on using airstones, and/or a waterfall? If you're not planning on using airstones, you'll probably to over-compensate and go more than 1000gph, to make sure there's enough flow to get DO to the center roots.
how did i come up with 70g? by knowing the dimension of my buckets, and what the approx water level would be by using a 10" netpot
roughly equates to ~60% full based off bottom of netpot and waterline either just touching, or barely below netpot
9x13g = 117g x 0.6 = 70.2g
and yes ill be using airstones, and a 110lpm air pump.
and how do you get 10gallons from a 13gallon bucket? you would have to be running the water level so high in the system, that first off, you'll end up killing the plant by having 100% of the rootmass submerged, as well as, if there is the slightest problem with flow, you would end up overflowing the buckets and flooding your room? 10g in a 13g bucket is neither feasible or logical? and i based my flow rate of ~750gph to achieve approx a 10x per hour turnover rate