Stick to a bristlenose for now. They stay relatively small and could happily live in your 20. Buying a fish for a tank you don't have yet is never a good idea.
Stick to a bristlenose for now. They stay relatively small and could happily live in your 20. Buying a fish for a tank you don't have yet is never a good idea.
For a 20GAL I personally like bristlenose plecos or rubber plecos. Both species stay small and their constant rasping keeps glass and rock work clean from algae build up.