mysterious fish death

Hey all, I'm absolutely devastated. Went to check on my tanks before going to bed last night, only to find the Cherub Pygmy Angel taking his last breaths. I'm at a loss for what happened as only a couple hours earlier he was swimming about as normal with no signs of distress ect. Please let me...

I have had two large-ish fish die in a week. Both in weird ways. Cleaner wrasse I found curled up in a corner gasping. When I went to fish him out he tried to swim but couldn’t. He had a weird puff of flesh at the join on his fin and it wasn’t working at all. He’d been in the tank since the...

Lost my first fish yesterday, absolutely gutted as my little tailspot was a real character and the tank feels much quieter without him. Looking for any possible advice on why he might’ve died? The tank mates were a clown and a hectors goby, all of which he would regularly swim with and get on...

Would like people's thoughts on this. I have been keeping a mixed reef tank for years now, and have always fed my fish with mainly frozen foods! Last night I fed them with frozen krill, and to my surprise a white feather was introduced into my tank via the frozen krill. The very next day my...