My fish are dying

[HomerJay]

I'm not sure why some of my fish are dying. I have a 2 year old tank of Brichardi and some other assorted africans. It seems that all of a sudden at least 4 or 5 of the mid size brichadis have died. These fish were at least one year old. They were offspring of my 2 original Brichardi. The only thing I changed was the sponge in my AC500 filter. I also have a Whisper3 filter and a power head for filtration. All parametes are fine. Ammonia and Nitrites are zero and nitrates look to be between 20-40. Just wondering if anyone has any idea what could have caused it. The tank is a 55gal. Everything looks normal, could it have been the sponge. I rinsed it before putting it in the tank.

[Harry Tolen]

I don't think it was the sponge. I am always suspicious of new sponges, and rinse them before using them like you do, but have never experienced any losses.

Has anything else about the tank been changed lately? New fish, new diet, etc.? Has the pH remained stable (bioacidification might have lowered it to a point that is dangerous for Rift Lake cichlids).

Also, what may seem like a silly question. What is the water temp in your tank? Sometimes a heater can malfunction and your fish will wind up in water that is either much too hot or too cold for comfort, without anything else appearing to be wrong.

[HomerJay]

Thanks for the quick reply. My temp is 80.6 degrees fahrenheit. It always hovers around this temp. I checked my ph last week and it was normal for africans. I have not checked it yet today, so I will do that. Also, I have not changed their food. I will do water change to see if that helps. They all seemed fine yesterday.:confused:

[HomerJay]

ph is 8.0-8.5. hard to tell exact color. Also, fish seem to be laboring a little bit breathing. Don't know what happened. Maybe something in the air? I have a sw tank though and they are all fine. Even the invertebrates, which would probably be affected before African cihclids. They're usually pretty hardy. I asked my 5 year old and she said she didn't put anything in the tank. I'm at a loss.

[Matt W]

I would take some water down to the LFS and have them test it...It is possible that your test kits are bad or expired....

Labored breathing could be an ammonia spike...

[HomerJay]

I was thinking it could be ammonia myself. I'll have to take a sample to my LFS. Thank you both for your ideas. I haven't lost any more fish today, since the water change. Maybe my ammonia kit is bad.

[scholar]

30-50% water change every three days, will keep your fish alive util you figure out what is oging on.

DO not stop the wwater changes. :)