Best Fish for a 20-Gallon Tank

Edited by Ivan F.

A 20-gallon is the size we most often suggest to beginners. More water stays more stable and leaves room for a small community.

How we pick: Species whose minimum tank size is within 10% of 20 US gallons or smaller. Group size still counts: always check how many fish a species needs.

Fitting the same tank size does not mean these species can live together. Check each species' tank mates before you buy.