LALALALALA I CANT HEAR YOU LALALALALA :duh::duh::duh::duh::duh:dont add any more fish to a tank that small.
How big a group? 3? I think 3 would be fine. They're not very active fish, are they?i'd rule out otocinclus... they're happier in groups. maybe a couple shrimpies or snails.
Arapaima?I also suggest against adding other fish. Regardless of how active other fish are, a 3 gallon is just too small. I'd go with snails or shrimp, or get a 10 gallon tank if you want to add more fish.
No, I just don't agree that it would be particularly overstocked with anything more than a single betta.LOL, an aquarium board troll?