I've heard that, that they will confuse them for bettas because of the tail. If you think he's passive enough to handle it, you could introduce some into the tank...But be on guard! watch to see exactly what he does for several days.
Aris - Pure white HM! 5 gallon.
Pheonix - Red VT with blue highlights. 5 gallon
Died of dropsy.
2 bettas to fill my divided 10 gallon
Filling my 35 gallon tank, going to be a sorority once i get money for decorations...and fishies...and plants...and meds, filter, heater, light...