I think another cichlid is a problem,because any other cichlid is going to be thought of as competition.
You might be better off getting something like a small shoal of swordtails or mollies.
These usually aren't seen as competitors and are a natural part of the habitat.
Check out my short video of a small pool in the Yucatan, although these cichlids are not convicts, they are cichlids with similar territorial and competitive attitudes.

You might be better off getting something like a small shoal of swordtails or mollies.
These usually aren't seen as competitors and are a natural part of the habitat.
Check out my short video of a small pool in the Yucatan, although these cichlids are not convicts, they are cichlids with similar territorial and competitive attitudes.