In SW in time you can learn to ID sickness and treat it pretty well.Yeah that’s what sucks about fish diseases most have similar symptoms and once you notice them it’s hard to treat if they’re hard to recognize. I was talking with my friend and we were saying we kinda wished if fish got a terminal disease they would just die immediately so we wouldn’t have to go through the stress of diagnosing the disease and trying different treatments, just for them to ultimately fail haha. However it’s very rewarding to successfully treat a sick fish and see them get back to normal.