Paradise fish(Macropodus opercularis) are beautiful, but unfortunately very aggressive. They are also labrinth fish, and like bettas must be able to get to the surface to breathe.
Optium tank temperatures are 60-70 F(15-20C) and need at least 20 G long.
When spawning they will kill everything else in the tank sometimes including the female if she can't get away from the male.
They will also eat anything that will fit in their mouths.
This is from personal experience and is backed up by my book on labrinth fish which I didn't find until after the massacre
If you have a tank big enough to set up a species tank they are gorgeous and very personable, will even eat out of your hand. They also spawn very easily.
Hope that helps
I have never even seen them at lfs's only in books. They both look great but that's about all I know and from what Ive read like to be kept by themselves with those of their own species. (Species Tank) like Butterfly said.