It might be possible JD lover. but only if there are alot of space for them to hide and get out of the way. Also depends on how the fish are. Some silver arowana might be to aggressive others not so much. My firemouth is calm as can be, barley every chases my acara or baby oscar. What size tank is the arowana going in or in?
Arowanas tend to merge in groups of five to eight; any fewer may show an excess of dominance and aggression. Some compatible fish often partnered with this fish are clown knifefish, pacu, oscars, plecostomus, jaguar cichlids, green terrors, gar, siamese tigerfish (datnioides microlepis) and any other semi-aggressive fish that cannot fit in the arowana's mouth.
Australian species are best kept singular in aquaria
Dude that Guy had like 10 giant fish in a 55g!!!! I wouldn't take any of what he have in his tank to put in mine was hoppin id get so good size cichlid ideas that can't be eaten by the arowana lol thought a groupd of 5-6 fire mouth be good bt guess not lolany idea of which cichlid will b big enough?