hey there Hiddenmessage, for yield the more plants the better, generally speaking, you can probably put up to six of those 10 gallons in there comfortably, even if they end up cramped 6 will be better than 4 which will be better than 2 or 3. 10 weeks of veg and you'll probably hit a high yield, but you'll probably only need like 8-9 weeks tops for those results. So pack them in there, get a big light and see for yourself 👊