So the LFS has killifish and they are really cool looking. They have one with a bent spine (looks kind of sad) but the guy says it doesn't seem to affect him. I was wondering what anyone can tell me about these. Do they have to be kept in their own tank (Newbie here, and "killifish" makes me think predator)? Or can I buy some and put them in my community tank? Thanks
Here's two pics. Sorry about the quality. They didn't want to hold still in the LFS tank.

EDIT: So I read somewhere that they are "golden killies" but that "golden" just means they really don't know what kind they are. Also, that they are jumpers. Can I keep two in a ten gallon with no openings in the top?