What's wrong with this danio? (pic)

[Danny-O]

Short Version:

It's bent!

Long Version:

So, I have seven zebras, purchased in January to cycle and be permanent residents of a new 33g tank. Everything is peachy in the big tank. Two weeks ago, I moved two zebras to be the only residents in a cycled 5 gallon tank (which housed neons while the 33g tank cycled; all tetras are now in the big tank). In have them in there to keep it cycled for a few weeks while I decide on my next fish for the 33g. (The 5g will be the QT for the new arrivals.)

Well, one of the two zebras in the 5g got to picking on the other. The other started sulking in the sunken ship and under the filter. The dominant zebra wouldn't even let the sulker feed. Just yesterday I noticed the odd shape the sulker had! (see pic). I don't think it had that unusual shape to begin with--all seven zebras looked and acted normally when together in the big tank. But I don't recall for certain.

Yesterday I moved the sulker back to the big tank, leaving the dominant by himself in the 5g for now. The sulker has perked up, chasing food and not sulking, though he's not as energetic as the rest of the danios.

Is he just starved or stressed? Or does he have some nefarious disorder?? I don't see any wounds or sores. Just the odd shape. I moved him back to the big tank thinking the aggressiveness of the other danio was his problem. Now I'm concerned I may have a sick fish.

33g and 5g tanks have 0 nitrites, 10 to 20 nitrates. pH has been 7.6-7.8 over this period in both tanks, 72 degrees in both.

 

[Aqualung]

To me it looks like the fish has injured it's spine somehow. Possibly damage from the aggression. Getting rammed in the midsection by another danio could cause an injury like that (those things are fast), or bumping into the glass while trying to escape is a possibility. Also 5 gallons isn't much room for an active fish such as danios, and it doesn't allow room for a school to even out the aggression. It's just my best guess, and if I'm right I doubt there is much you can do about it except hope it heals.

 

[bert501]

For what it's worth--I saw a bunch of danios that looked just like this one in the tank at petsmart.

The "extremely knowledgeable fish keeper-guy" told me they were bent because they were a cross between "regular zebra's" and giant ones! :thud:

I think Aqualung's reply is probably the right answer--this is caused by some type of injury that will hopefully heal.

 

[dorkfish]

I had a male drawf gourami that looked just like that. It is'nt a disiease so you don't have to worry about your other fish however that one probably won't last more than about 3 months. my drawf gourami got like that because it got beat up by a three spot gourami so it could be agression that caused the fish to look like. If you suspect agression to be the cause watch your fish until you see somebody atacking the zebras, then remove fish from the tank to solve the problem.

 

[monkey_toes]

I've seen a lot of fish like that in the stores. I've noticed that they're always captive bred fish, never wild-caught, so I assume it's either damage incurred as fry or caused by inbreeding. Either way, those fish should probably be culled before they make it to the store. That said, as long as he can eat and swim normally, he can probably live a normal life if the others will let him be.

 

[fish_breeder_05]

he is now a feeder in my book

 

[Danny-O]

Update:

I euthanized the poor beggar today. His "bend" become more pronounced. He appeared to be paralyzed in the tail, using only his pectorals to swim. He was even unable to chase the food flakes. He would lay forlornly on his side on the gravel after short, erratic swims. It appears it was a physical injury rather than a pathogen.

R.I.P., friend.

Meanwhile, the authorities are getting a statement from his tank mate.