a one eyed albino ruby oscar, a tiger oscar, a baby lemon oscar, 2 common plecos one 5 inches one 7, a green terror, 3 bala sharks, 7 red head tapajo, 2 baby jaguar cichlid, 2 firemouth, 3 pearl cichlid.
Don't know about bichirs, I've never kept them, but here are temperaments of the fish above, and some of the potentially bad combinations:
Oscars-- Temparement variable, can be aggressive, some are puppy dogs. Don't like to be crowded and can react violently if they are. Friend of mine in the 1970s had an Oscar in a tank with a Jack Dempsey and convict cichlid, forget exact size of the tank, but the Oscar quickly outgrew the other fish and killed them both overnight one night--- that's the trouble, which is how
fast it can happen.
Green terrors-- Temperament variable, anything from mild to highly aggressive. Besides the individual green terror, a lot depends on size of tank
and other species in the tank. Best with fish that don't look similar or that won't challenge it, they're not a fish you want to provoke.
Jaguars-- Large, aggressive, predatory toward smaller fish. Bad idea with the geo red heads. Except in a very large tank, bad idea with something like pearl cichlids or green terrors which don't like to be pushed, it can end in big time fights.
Bala sharks-- Get large, but are also shy and easily intimidated or stressed by large, aggressive species. They actually like to be in groups, but can be okay alone in a peaceful, non-threatening tank.
Red head geos-- Social fish, especially when smaller or juveniles. Active but mild, can be pushed around by even other comparatively mild fish if competing for territory, Guianacara, for example. Normally quite healthy-- except when stressed, stress can make them sick quickly. Simply should not be in a tank with firemouths, pearl cichlids, or jaguars. Oscar or green terror possible, would depend on the tank and individual fish.
Firemouths-- Temperament variable. Can be territorial or aggressive when they can get away with it but also easily intimated by tougher fish. Bad fit with jaguars or pearl cichlids, can be a bad fit with green terrors.
Pearl cichlid-- I'm assuming you mean Brazil geos here. Chunky, aggressive, sometimes bellicose. Apt to bully some on your list, apt to fight with others.
Common plecos-- Get big, produce tons of waste, eat less and less algae as they age, sometimes aggressive if they can get away with it.
Imo a 1000 gal tank build can potentially be a dream tank, but I'd spend some time watching youtube videos to get a sense of combinations that work and look good together so you don't end up with a nightmare.
