My LFS occasionally gets bluefin killies in their feeder tanks, and I'd like to keep some. I don't have a tank that could be set up to exclusively hold them, but I have a tank that's lightly stocked and has a slot for a peaceful shoaling fish. They aren't native fish, but I think they'd get along with the bluefins. Believe me, I would have a small-natives tank if I had the space.
The tank is a 29 Biocube, currently lightly planted. I'm working on growing moss and such in the background in order to help fish fry survive. The current stock is 3 amano shrimp, 4 glowlight tetras (used to be in the big tank, temporarily-housed green sunfish ate the rest, will be getting more) and 4 Betta albimarginata. B. albimarginata are a small species of wild-type betta, about an inch and a half long at full size. They display at each other, but they don't get in real fights. They're very peaceful and mildly timid, so anything more boisterous than a glowlight is a bad plan.
The main problem I have is this: bluefin killies don't live long. Is there a reliable way to get them to spawn in a community tank, if I provided a big bundle of moss to act as a spawning net/fry refuge? Also, anyone have any advice for getting them to live a bit longer than two years?