HELP! NastayNatron's tank

[lo_yyc]

Hey everyone,

My roommate, NastayNatron, is on vacation right now and I'm taking care of his tank (or at least trying to).

I was out last night and when I came back, I found 1 dead fish and I haven't seen a few of the other ones yet. I know that Nathan mentioned once or twice that sometimes if 1 fish dies, it is toxic to the rest of the ones in the tank and it can kill all of them, so I'm worried that some sort of chain reaction started while I was gone.

The one that I know was for sure dead (that I've taken out now) is the Foxface Rabbitfish, and the ones that I haven't seen yet are Anthias (I don't know what kind - I know there are 3 and 1 of them is a male square spot, but I don't know what kind the other 2 are).

The tank is looking pretty cloudy, but I checked all the things I know how (emptied the skimmer cup yesterday, checked the refugium, no leaks under the tank, and I've cleaned the glass, but I know that probably won't do much) and it's still pretty cloudy. I'm sure that's because the tank hasn't had a proper water change since Nathan left, which was a week ago I think (I just got back from vacation myself).

Anyways, he said that someone would probably be able to give me some ideas. I guess that I know the ideal thing would be to do a water change but I don't know how to do it exactly and I'm not sure if he has any salt water mixed or not.

Anyways, I really appreciate the help, I hope I'm posting this in the right place.

-Lauren