I think its either fighting or spine deformity(? don't really know if theres a technical term, but its most common in older jack dempseys where they grow old and they look sort of crooked and their bottom lip just hangs open). It seems some cichlids get old and then they just can't close their mouth anymore. I have seen similar problems with Jack dempseys, Oscars, Jaguars, and a couple others. But mostly with the first 3.