fish attack

Hi all I have all in one sump system 25gallons tank with 2 true percula with it yesterday one of the fish is get strucked in acrylic at overflow I help him to taken out of the it. It got a wound at right side gills and today it is take heavy breath. I don't know what to do with it plz guide...

Hi, I've added 2 cardinals to my 450L tank, they have been in there since Saturday, and this AM I noticed that one was looking a little raged. Now I've watched fish A attacking (the now raggedy) fish B. What should I do? They are all that is in there atm, will this stop once pecking order is...

I have a 40b with a maroon clown and a watchman goby. The last two fish I had were a damsel (lasted 3 days) and a six line (lasted 3 weeks). After looking at every option on what is going wrong with newly introduced fish my best guess is the clownfish attacked. The symptoms of both fish were...