I'll second the asking your LFS. When I sold to individuals I sold angels, brevis, guppies (you'd be surprised how much a quality harem can sell for), a. cacatuoides. When I started sellling to just LFS, I switched to brevis only. They wouldn't give me crap for any of the others, but $10 a piece for 1/4" fry... which I could make about 50 of a month. now I will occasionally keep a batch of apisto fry and raise for fun, but since I don't really pay a whole lot of attention I get maybe 10% survival rates.