I'm under the impression that each plants needs around 10 gallons to reach maximum size. How big can they get in 5 gallon buckets? How often would you need to change / top off nute mix in the later thirsty flower stage?
I reckon if you grew it well 2-4 oz in 5 gal bucket,they can still get fairly large believe it or not. Depends on the nutes u feed but I keep feeding real hard in the beginning of flower stage with growth high (n) nutrients during flower stretch and switch to a flower feed about 3 weeks into flower. Many folks do it differently but that works for me.
Not sure where you heard of “max size” and 10 gallons, that doesn’t make any sense. So many variables, u talking dirt, hydro, etc? Btw I’ve grown 3/4 lb plants in 3 gallons of promix. Just means you need to water more often.