Mysterious Fish Deaths

[dbreeves]

Hello everyone,

I am writing to seek your suggestions/hypotheses.

While I was away for the last five days, I lost a few of my fishes (a Tomato Clownfish and a Red Stripe Angelfish). When I discovered their carcasses, I immediately removed the dead fishes, changed 25% of the water, and did some basic water chemistry.

Nitrates, nitrites, salinity and pH were all normal, while ammonia was slightly elevated, which I attributed to my partially decomposed fish friends.

All of my fishes were alive and healthy when I left, and I put a dissolvable food pyramid in the tank that should have taken care of them for at least three days.

This is a very well established 20 gallon aquarium (>2 years) and I had kept both of these fishes for over a year and a half.

I'm stumped. Have you experienced anything similar/have ideas on the causes of these deaths?

Thanks!

 

[b0bab0ey]

What kind of "dissolvable food pyramid" did you use? I'm not familiar with any suitable for s/w fish. It's possible it just dissolved into your tank, and left uneaten, caused an ammonia spike. If you're away from home often, I would invest in a good automatic feeder. Or next time just don't feed for 5 days - the fish can take it.

Also, what did you do to compensate for evaporation? Is it possible your SG rose too high while you were gone?

 

[dbreeves]

I used an "API Weekend Pyramid." I have used this brand before without issues, and the packaging claims that it is suitable for saltwater fishes. However, I am still a little skeptical over the feeder.

I don't have much evaporation in this tank, and the salinity did not change over the duration of my trip.

 

[rssjsb]

I have an autofeeder on my big reef tank, but my smaller tanks have gone without food for up to a week and the fish were fine. The only losses I've had while away were related to an unexpected heat wave.

I agree with Bobaboey that autofeeder or fasting is better if you're only going to be gone for a few days.

 

[aandfsoccr04]

Could also have been a temporary loss in power that would cause lack of oxygen in the water with no water movement.

 

[dbreeves]

Yeah, that was my initial thought, but all of my clocks were correct when I got home.

I've noticed that my pseudochromis is starting to swim a bit erratically, rapidly breathing, and his coloration almost seems dull.

 

[dbreeves]

Update: It appeared that the pseudochromis started to develop ich very quickly yesterday morning. I treated the tank with an ich medication after work, but the fish was looking pretty bad and it died some time in the morning.

Since the water change, the water quality has been immaculate, so I assume that I have a parasite problem.

My first guess was ich, but I have never seen ich develop this quickly. However, I suppose the ich outbreak could have resulted from some other stressor to the fish's health...

Down to one fish, a canary wrasse, and he looks perfectly healthy.