Any livebearers.
It's because I fear being overwhelmed by babies that I have to kill because they don't find homes. Already happened to me with cichlids many years ago and more recently plecos.
I don't like destroying unwanted baby fish, plus it gets me lots of hatred online for being such a bad person who kills pet fish.
Cichlids. Why not?- they sound like they are very hard to keep healthy. Like there's a magic trick to being able to raise them. That, and I don't know if I could watch fish that bully eachother. Wouldn't be relaxing to watch the tank, if they were after each other constantly.