I have a shehunkin and a comet of the same size in a large glass tank with a good filter which also produces bubbles so the water is clean and aerated. I clean them out every couple of months before the water gets too dirty.

Up until now, they have both been extremely healthy fish, almost with personalities! Every time I walk past the tank they go mental and swim about very fast wanting to be fed. They are the most active fish I have ever had!

Anyway, the shebunkin is in normal, fine health, fins erect, lots of movement, health appetite, good colour, clear eyes etc. The comet also boasts these healthy features, but over the last few days I have noticed a worrying change in his physique...

He seems to have a bulging stomach! Either side of his "waist" is bulging, it look like he swallowed a mini balloon! So much so that his scales look like they stretched a bit. He seems happy in himself, just sleeps a bit more than the other fish now, but still gets excited if I approach the tank.

I have not fed him for almost two days as i wondered if I fed them too much, (although the other fish is fine) so I tried to allow him to pass whatever was "blocking" him, but this has made no difference. I don't think he has passed any waste for a while, I looked this morning and he had a thin white almost clear dropping...I'm convinced he is blocked in some way. I suppose there is nothing I can do for him really? I wondered if he somehow swallowed some gravel, but I'm sure the gravel I use is too big. He is swimming fine, so it's not his swim bladder.