Stock 20 gallon?

A DEFINITE BIG NO.
 
Couldn't agree more : a) tank too small, for the labs alone b) tank wrong shape (want long tank) c) labs and Angel = dead Angel.

If you want africans in a 20, consider ocellatus or similar shell dwelling cichlids from lake tanaganyika. www.cichlidforum.com ; some suggested mixes here.

I guess you could try leilupi, but I don't know that a 20 high is enough floor space for 4. Perhaps 1 male, 1 female.

I think you'd probably get away with a pair of rams, seeing as you ask, although a 20 long would be much, much more suitable.
 
How about a pair of apistogrammas?
 
I guess you could try leilupi, but I don't know that a 20 high is enough floor space for 4. Perhaps 1 male, 1 female.

I was thinking more along the lines of buying four, so you can get a pair. Many juvinile Tanganyikans are hard to sex when they are little. This is my nearly surefire way of getting one of each. (though, I have seen this method get someone four males!)
 
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