Join Date: Oct 2010
Location: Victoria, Australia
Most breeders don't seem to recommend it. Some of the splendens complex species can be just as aggressive as the ornamental form. Based on what I've seen on FB groups, breeders of Betta mahacaiensis and other splendens complex species, will separate males out once they start to reach maturity. Either that, or they will have many related males in a large aquarium.
I wouldn't risk it in a smaller aquarium with a smaller number of males. I'd also advise against housing a male/female pair together unless you intend on breeding, as most wild betta species are very easy breeders, and the constant cycle of courtship and spawning can take a toll on the pair.
There's nothing wrong with keeping a single male Betta mahachaensis.