Hello everyone I have a maroon with a gaping mouth. He is the peace keeper Swims towards aggressors but that’s about it. I have never witnessed him bite though he will tag me lol. It could be that I just miss this behavior idk. I did recently add some tangs and cardinals and everyone seems happy and healthy. I’m wondering if maybe he swam into propeller of the jet though I would think that would be instant death and I see no wounds. I have kept a very close eye on parameters due to a cyano bloom and a previous fight with Dino that just ended days ago. This is a established aquarium. Any thoughts? I boosted oxygen and turned lights down to help reduce stress I can’t really tell if he is breathing heavy and I can’t see anything in mouth.