I have a concern with some of my fancy goldfish that seek the surface after being fed. They sit there gulping air in and I am concerned that they may get swim bladder issues from it.
Why do they do this? I have plenty aeration (2 Airstones and a lot of surface agitation). Also it is only 4 of them that do it. The rest just swim as regularly.
The tank is slightly overcrowded. They are in a 140 gal while I reorganize their 190 gal. but nothing extreme. Also they did the same when they were in the large tank so I don’t expect it to be down to overstocking.
With only a subset (of the same species?) doing this, perhaps your hunch is right that this could be an indicator of something specific to those individuals, like a disease.
My only other guess would be if you’re way overdosing dechlorinator.
I can’t overstate how not an expert I am, though.
Yeah I only have fancy goldfish in the tank. Not ideal to mix with other species. But I don’t use dechlorinator as the tapwater here has no chlorine or chloramine. I feel like it’s the more round bodies goldfish that I have that get affected and also the smallest size wise but maybe they have over fed?