Pop Eye

[VTDrew]

So I went away for about 2 days and came back to a Buenos Aeries Tetra with both eyes popping. Its a new tank, I just completed my second week populated (1 week unpopulated).

Tank Stats (cycle stats from 24 hours ago):
56 Gallons
ph - ~7.0+/-.2 (I have trouble with the pH colors)
Ammonia, Nitrites, Nitrates All Zero
Did a ~20% Change after test.
All other fish appear A-OK.

Previous Stats (Cycle stats from 11/29, verified by test at LFS, all number were same between me and them that day)
7.0/0/0/0
Phosphorus (I can't test for this, LFS only) = 0
Did a 20% Water change 3 days later (I do 20% per week).

Population
5 Zebra Danios
3 BA Tetras
Deaths To Date - 1 ZD on day one populated

Water source - drinking/tasting water from a beverage development lab (you don't get better then this, a lot of people I work with have tons of success in their tanks using this water and treatment routine) treated for Chlorine.

My other tank gets the same treatment and everyone seems fine...actually this tank recently recovered from disaster. (Yay!)

When I got home, I got ready to "net him." He was gasping on the bottom and was ready to euthanize. Once disturbed he perked up a little and went back to schooling with his buddies.

I read that both eyes is likely infection. I am sure as hell it ain't the water. I do have two bubblers in the tank and read that swallowing a bubble could cause CO2 poisoning. Which leaves me to two questions:

1) Euthanize immediately or give the little sucker a shot being he perked up.
2) Shut off bubbles?

I am not going to start medicating a brand new 56 gallon tank still cycling. I don't want to pull my filter out with all its juicy bacteria just yet, medicating for columnarus is what put my last tank in disaster mode when the cycle crashed.

 

[ColR1948]

Could try putting in a hospital tank and add Epsom salts.

 

[DrRob]

Could have been a mini ammonia or nitrite spike. There'll be low level ammonia in a cycling tank (has to be really, otherwise it wouldn't cycle) and it surges occasionally. When you come to test it's started to clear already and is back below the level that hobby level test kits can detect. Those spikes can then leave the fish open to infection, hence the pop-eye. I've heard of swallowing bubbles before, but have never actually seen any definite cases. Doesn't mean it can't happen, but I'd be surprised if that was responsible.

You could indeed, if you have the resource, move the fish to a hospital tank and treat there. Otherwise, personally, I'd up the water change rate, which is a pain, but I've always found it stopped any more issues.

 

[VTDrew]

Well, the fish died overnight. My 20 gallon is destined to be a hospital tank but my fish in there are not hardy enough to go into a new tank and therefore is not ready yet. Some inhabitants will stay to keep the ammonia cycle going.

I had some odd suspicions about this fish since day one. Perhaps this was just something destined to happen. While I didn't plan on putting any new fish for another 2 weeks, I think I'm just going to have to get a new one to keep the tetra school happy.