They have been found breeding close to saltwater reefs in full marine conditions. But they're not the only cichlid that can survive in saltwater... There's saltwater flowerhorns that live in reef tanks (youtube it) which leads me to believe that when acclimated properly (might take several months of acclimation, starting at very young age) many other cichlids can be converted to saltwater. This is believed to be stressful and not healthy for the fish at all, most of them die and those that survive supposedly have a severely shortened lifespan.
Why would anyone want to do this is beyond me though... it's like trying to house parrots and bats in the same cage just because both can fly. I guess people have way too much time on their hands.