Otocinclus

[kreynolds1153]

My oto went from having a long body with a big belly to now having a "s" shaped body. What does this mean? What's going on with him?

 

[coralbandit]

Curved spine is a symptom of many diseases. Often bacterial.
Most often when noticed it far too late to save the fish as internal damage has occurred so severely it can be seen from outside.
Best to remove the fish before it dies.If other fish are allowed to pick on the carcass the disease will be spread for certain.

 

[kreynolds1153]

Do I do a euthanization or what?

 

[coralbandit]

I would. But if you have a tank to attempt to treat him you can?
Ice cubes in a cup of water chilled will pass him in seconds.
Sorry about your fish, watch the others closely.