betas

Many fish can coexist peacefully with bettas. Platies, guppies, and mollies are no exception. Some people have, however, had problems keeping male guppies with male bettas, so if you wanted to have guppies with them, I would only have females or short finned males like that of the cobra strains.

Most tetras, cory cats, kuhli loaches and other peaceful, none labyrinth fish species and coexist with bettas well also. Avoid fin-nippers like tiger barbs though.

Hope this helps :)
 
bettas have problems with thinking other colorful fish are male bettas but other than being sure the betta can't eat the other fish(neons have become lunch for a betta I knew) and the other fish won't pick on the betta you have lots of possibilities
 
Danios can live with a betta as well, as long as there is enough room then they would be okay. Bettas prefer some current, and a planted tank. So honestly, if you had enough room you could keep a lot of different fish with bettas, although be more cautious with brightly coloured males of approx the same size (ie: male guppies!)
 
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