Thought you might like to read this little bit of info which I have found here:
"FLAGFISH
These are great little fish that look like a platy/cichlid cross (Biggest we've grown is 1.5 and up to 2"), we have them in the same pools of water with our Singapore Shrimp and SAE's, and they all get along fine. We have also had them with other Platys, Mollies, and South American Cichlids too. However, they seem to hate frilly, or long-tailed fish, we had some bettas in a pool for just one evening. and by morning a school of flag fish had eaten every one of them including most of their skeleton so this showed how aggressive they can be..."