"jess" wrote in message
oups.com...
I am new to fishkeeping and am not sure what to do for the best. I
noticed this morning that my less than a year old comet, Dale, is
swollen mainly on the left side above the pelvic fin but perhaps a bit
on the right side also though not as much. He is sitting at the bottom
of the tank but will come up and swim around if I lift the lid then
when he realises nothing much is going to happen he goes back down
again.

This doesn't sound too good.

He is still eating and the water quality is within ok limits.

Can you tell us what you checked so far? How is the Ammonia and Nitrites?

I have only had him and his tank mate, another comet, for 11 days so
cannot believe something has gone wrong already!

Things can go wrong very quickly, see
http://faq.thekrib.com/begin-cycling.html - in an uncycled tank. The
swelling doesn't sound normal. You can also check out www.koivet.com for
more information.

Dale has always been
the slightly smaller of the two and the quieter and doesn't eat as much
but seemed perfectly healthy until this morning. I don't see any
raised scales or gasping or areas of soreness so what do you think it
could be and if it is possibly the start of a bacterial infection
should I start treatment straight away just in case. If so what to do
and should I isolate him or leave in tank to treat.

Before you do anything - what are the ammonia and nitrite levels? What is
the PH of the water? Was if very different than the water at the petshop?
--
ZB....
Frugal ponding since 1995.
rec.ponder since late 1996.
My Pond & Aquarium Pages:
http://tinyurl.com/9do58
Troll Information:
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