I dont know what has happened in my tank... first my tang died and now I came home and both of my clowns died at the same time. All the water parameters are fine. I had both of those fish for a couple of monthes and they died the same day. The two dominoe damsels both are still alive though. Could this be anything to do with not changing the water often enough? Ugh Im new and this is really frustrating like 70$ down the drain and a sad tank.