HELP! BLUE DISCUS TURNED BLACK, CLAMPED FIN

Question
I have 5 discus, 46 gal bowfront, 82 degrees, ph 6.8, low nitrate, (tank is two weeks old) ammonia is a bit high but I have ammo lock and two bags of ammonia filter with bio bag and big sponge in my (I believe aquaclear) 72 gal filter.

suddenly my blue discus turned black. one fin is clamped to it's side! He seems extremely timid... usually this fish was out in the open. something has changed for him. other discus seem okay.

he was eating just yesterday and seemed okay. I've had these discus for about a week. Never any problems except in the first few days they were shy. they accept me as their keeper now... so everything is fine, except for this sudden darkening blue discus. don't see any spots or white excrement, nor white mucus on the outside of the fish, or fin rot. seems to me he just turned black over night... and his one fin clamped. I catch him hiding behind the filter, even though I have lots of fake/silk plants and areas for him to hide. Don't want him to die! Will his blue color come back from black?

I put in the correct amount of dosage for API aquarium salt, and I did a dose of melafix today and a 20% water change. also have just the moon lights on today to keep the waters calm and unstressful

is he stressed? or could it be the black plague?

anything I can do to help him shake it?

thank you!

Answer
JC,

You need to remove him right away and place him in your hospital tank. He is stressed and on his way down and fast. Treat him with Acriflavine solution plus salt. Your nitrates need to be at zero. One discus needs to have 55 but would do better in a 90 gallon. You have too many fish in there. In order to keep them healthy you either need to return 4 of them to the store or buy a much larger tank.

Here is a great website on the plague, he tells you how to helps them. Please get them a larger tank or you will surely lose them all.

http://members.tripod.com/discus_unlimited/article/plaque.html