same here, i think it depends on the betta and what else is in the tank with him. ive kept them with
Poecilia sp., but one kept in a tank with 4
Botia kubotai, a
Serpae Tetra (rescue) and a true
SAE, and against all odds he left the Serpae alone and the Botia ate a few bites of his fins.
typically you want to go with fish as partners with bettas that are less flashy than other bettas.
you may possibly be able to keep two males in a very very large system with tons of floating plants but expect them to rip into each other on occasion. no less than 3 females in anything less than 20g and even then make sure its a long with lots of plants and decor.
also, the only way to help with ammonia burn is to do water changes. routinely you want to do at least 40% every 2 weeks on even lightly overstocked tanks but if your tank is not done cycling or you did soemthign to disrupt the cycle then you shoudl be doing as much as daily water changes to keep it under .50ppm.
Sneakey, ive kept my bettas (that i havent lost to genetic issues) for an average of 4 years. i feed live black worms, pellets, mosquito larva when its in season and gnats when i have the honor of having them in my kitchen.
typically i feed every other day. of course those are all ones ive kept in dedicated tanks with at least a filter and live plants (yes, im a geek. i know i have a problem!!) you know what, i think im just going to send you a PM. i dont want my fish geekyness getting out!!
-ash