I would think it's most likely a white/or pink tilapia, they are more common in the canals than the red devils which is super uncommon in these canals.Whlie I'm not discounting the possibility they could be Talapia, I'm more inclined to think they are a feral populatiom of A. labiatus. The color and lip discription fits more closly in my estamation. Not Midas (Amphilophus citronellus) but Red Devils (Amphilophus labiatus). It will be interestiong to get a pic for proper ID. Looks like you have your own UFO (Unidentified Fishy Object) hunt going on. Good luck with getting an ID.