A general rule of thumb from my aquarium days is 2" of fish for every 1 Gallon. This info was relative to tropicals with good filtration and aeration in a seasoned (bacteria rich) aquarium. From experience with pond fish I would cut this number in half to 1" per gallon max starting out and not letting it exceed 1.5" per gallon if you get growth. I once observed 4 4" bass devour 100 minnows in 3 days. They are eating machines. This resulted in very poor water quality in a tank with excellent (reef tank) filtration.



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