In my short length of time trying to feed train SMB, I found it was very hard to keep fish "in" the tank. I had no cover or netting and learned real quick on that.
I would guess the number of fish in "X" gallon tank would become more of a factor in high numbers. Temp would play a role in how often partial water changes would be needed plus what type of feed. If minnows are used water quality would remain better, longer.
How many fish and how big of tank??