I lost a beautiful butterflyfish that was doing great in my aquarium! I was so proud, I bought the fish on an impulse to find that its a difficult species to keep, well it was doing great, it was even eating flake food! And one day after doing some cleaning I left a powerhead on in the tank that I usually leave off (because it had no guard in place) and durring cleaning I had twisted the powerhead so that it pulls in water from the side, soon I found myself with a dead fish... that was a sad day... it really turned me off to salt water, luckily I am working my way back to the point where I can buy new stuff. But just thinking about it is so sad.
Good luck to your fish, I cant wait untill I have my clown fish!
-max