Help with small tank

bettas don't come from shallow puddles like people think. i think shrimp would work best. it is a bit small for a betta cause they do like some swimming room. just cause they can live in a cup doesn't mean they should. the three together would just kill each other
Very true. The more room for a betta, the better IMO.

I still say shrimp.
 
go with shrimp, if you add snails that greatly increases bioload
 
AquariaCentral.com