Quarantine Tank Disaster

[Doc7]

I have a 15 gallon tank in which I had 7 juvenile cardinal tetras and 12 juvenile pygmy corydoras for the last week (of 4 weeks QT).

I perform water changes daily or every other day with dechlor.

Fish have shown no sign whatsoever of illness - no odd behavior, no markings, eating properly, swimming actively etc. Observed them last night for a while and everyone was as fine as ever.

This morning I woke up and had lost 3 or 4 of the tetras and 5-6 cories. Dead, stuck to filter or on bottom of the tank. I immediately removed the bodies and performed a 50% water change with 5x dose of Prime. Some of the remaining fish look fine and some look distressed.

I tested the water which came out of the tank and it was 0 nitrites 0 ammonia.

I have come to 2 possible causes and wondering if this sounds what could have happened:

a) I put in a new heater last night because the old one wouldn't go below 80F even with it at the lowest setting. Is it possible the new heater has an electrical leak and shocked the fish? Temp is 78 so it didn't plummet or anything.



PLEASE CONTINUE BELOW - aquariacentral not letting me really post tihs at once i am not sure why

 

[Doc7]

b) I may have contaminated the tank with soap or some hardcore scrubbing/cleaning powder while doing dishes ,the cat box, and some tank items right after.

If that is the case is my bio filter screwed as well? I can move in media from another filter and will do so before I have to LEAVE tonight for thanksgiving stuff...

thanks for any suggestions as to what could rapidly destroy this many fish....

 

[nerdyrcdriver]

wow, that sounds pretty bad. Do you have a multimeter? If you did you could test for stray voltage in the tank. Other than that, I dont know what else to say. Wish I could help more.

 

[Lab_Rat]

I would guess option A. I had the same thing happen about a month ago, wiped out every single fish in the tank. What brand was the new heater?

 

[Doc7]

The remaining fish are all either dead or dying (in the 4 hours since I went to work and got back w/ early dismissal). This is the most distressing image I have ever seen in my tank. A pile of dead pygmy cories, and tetras stuck to the the aquaclear inlet. I am sickened...I have never lost a fish to disease (never even had one get infected) and I am just shocked that I had a total tank wipeout in a 13 hour span. A month after dealing with power outages and 15 degree temp drops, messing with CO2 for the first time etc in my other tank, and I've never once outright killed a fish due to negligence or failure to monitor illness.

I'm ending it for the ones who are laying on their sides on the bottom gasping. And breaking down the QT until after Christmas when I will be able to deal with this again without any long weekends to foresee.

My other 2 tanks which get the same food and tap water are fine (20+ fish between the 2 tanks). It had to be a cleaner, or something on the heater that came in, or what I don't know. I will hook up that heater to a bucket with a thermometer with memory on it and see if it is functioning properly.


God I wish I knew what went wrong so I don't do it ever again...

 

[Doc7]

I would guess option A. I had the same thing happen about a month ago, wiped out every single fish in the tank. What brand was the new heater?

the new heater i put in is a Marineland...

 

[Lab_Rat]

My heater that zapped my fish was a Fluval M. When you put your hand in the water does it tingle?

 

[EmilyMarie85]

I would lean more towards option B - I think option A would have taken them all out at once (?) and survivors wouldn't be on their way out now?

 

[nerdyrcdriver]

Put the heater in a bucket of water and see if it tingles a bit. If it does, then you might have stray voltage in your tank.

 

[fishhed]

hope you find the problem. +1 with B.