this is about 18 angelfish in a 100 gal freshwater aquarium

Question
Hello Chris...i certainly hope you can offer some advice.  my problem:

angelfish at top of tank gasping for air (12 out of the 18). my angels are a mixture of orange kois, marble,etc...14 different "kinds".

this is a long story so please stay with me...
i was having an algae problem in my tank...so i purchased ALGON on the internet (natural stuff in small bags that you hang in front of your water output from your filter...in my case, a powerhead). the directions say to remove the charcoal from my canister filter, so i did...4 weeks went by...i changed the 2 bags every two weeks..my tank has one large canister filter and 2 large powerheads (one on each side of the tank) connected to an undergravel filter...plus i have 2 bubblers for additional oxygen.

i woke up one morning, turned on my 220 watt fluoroscent lighting system and noticed that 12 of  my angelfish were gasping for air at the top of the tank...and 3 were covered with slime.

facts...nitrites and ammonia registered 0 when testing...ph was 6.8 (no change)...plenty of oxygen...thought it was gill disease...treated with marcyn and tetracycline...so far for 3 days...no improvement.

then, i thought it could be potassium poisioning from my home water softener...since i removed all charcoal from my filter and charcoal filters out potassium..so i replaced the charcoal and hung a bag of charcoal in front of my outgoing water from one of my powerheads...i also treated the tank with COPPERSAFE thinking it could be Chilodinella...well, the slime is almost gone and the treatment has been going on for 3 days...with little improvement...i have lost one fish..a rare red ghost angelfish...my favorite

since all of these meds can be used together...per instructions...the tank is not overmedicated...i feed them twice a day with blood worms...they are not overfed

my algae problem is solved...chinese algae eaters are the best!!...but i still have the fish at the top of the tank problems...i do 2 water changes per week...20% each time...(angels must have this)

i only have the angels in the tank besides the algae eaters (7)and 1 bottom feeder.

can you help...oh please oh please...best regards, john weber

Answer
Hi John;

I'm so sorry this is happening to you and your fish. Especially for the loss of your favorite. That's really a shame.

Your maintenance schedule is awesome! I wish I could get other hobbyists to do half as well. Obviously dirty water isn't a factor.

The symptoms appear to me like "Angel AIDS" or "Discus Plague". Same disease, just described for two different fish that can be infected with it. It is a devastating condition that is very difficult to successfully treat. I will include some links at the bottom here for you to read and get more info about it and see what you think. Since your bottom feeder and algae eaters are not affected, I suspect it is the plague. It can come in from live or frozen food, new fish, plants, etc. Discus develop it in a shorter time, while angels can take 7 to 10 days after exposure to the pathogen. Columnaris often attacks as well, as the fish are under stress from the plague.

One thing that seems to help is aquarium salt. Salt also kills columnaris. They need one teaspoon of salt per gallon of water. Add more salt only for changed water during a water change. (If you change 20 gallons of water, add back 20 teaspoons of salt.) Instead of those expensive little boxes of salt at the fish store get the uniodized rock salt sold for ice cream makers. Look at the ingredients to be sure it is pure salt and there are no other additives. Grocery stores usually have it.

Also, turn off the aquarium lights. The fish are sensitive to them while sick with this. Raising the water temperature to 85f also seems to help.

Here are the links for more info;

http://www.max-discus-dream.de/mddnew/DiscusPlaque.html

http://fish.mongabay.com/diseases.htm  (go to the bottom of the page)

http://www.aquaria.info/print.php?sid=34

http://www.aquaworldaquarium.com/discus_plague.htm

http://www.sunrisetropicals.com/id11.html

For Columnaris;

http://www.aquaworldnet.org/ASnewsletters.html  (scroll down about 1/3 of the page)

http://freshaquarium.about.com/cs/disease/p/columnaris.htm

I hope your fish start feeling better soon. I wish I had a "magic pill" to recommend, but this is often a 'trial and error' kind of disease. Our store experienced this horrible angelfish disease in the 80's when the commercail fish farms had such devastating losses. It was recommended that if private breeders had healthy uninfected stock, do not mix commercially bred angels or discus with them. It has not reared it's ugly head in such severity in many years. The theory is that most fish are immune to it now. The more delicate strains (albino, gold, koi) seem to be the most affected. Their immune systems are weaker and more easily compromised. The point is, I understand what you are going through. Not fun........

At Your Service;
Chris Robbins