This kind of reply is exactly why I don't like trying to help people on the forums some times. A copepod population explosion big enough to visually cloud the water, if that were really a thing, would be the result of something. That something being excess of nutrients in the water. It is not a common thing. A bacterial bloom or an algae bloom are both more common.
You can give that dead skeleton as much time as you need but it is dead as it gets. If you just keep saying your water parameters are "fine" then we can just assume you are not actually testing anything. If you want help, take the advice you are given, quote actual numbers and tell us what kits you are using to test. Galaxea is a very hardy coral. They usually kill other corals and are quite hard to kill themselves. No one is unlucky keeping any coral. There is no such thing as luck in coral reef keeping just knowledge and applying that knowledge consistently paired with proper husbandry practices. The things to always look at when troubleshooting issues are Water, Light, Flow.



