Yes it looks like finrot to me. It is usually caused by poor water quality
so you should test for ammonia, nitrite and nitrates a.s.a.p. Ammonia should
be 0, nitrite 0 and nitrate under 20. Anything above this isn't safe for the
fish and will cause health problems. Sometimes just getting the water
quality absolutely perfect can stop finrot in it's tracks, but to be safe
get your water perfect and add Melafix daily. This will aid healing and act
as an antiseptic. The melafix wont hurt the fish in the main tank and if the
water quality isn't quite right you need to sort that out there anyway so as
long as there are no other symptoms I'd leave him where he is.
Mel.

"Jon Pike" wrote in message
. 159...
http://members.shaw.ca/anonomoose/fins.jpg

From what I've seen of fin rot pictures online, there's usually more red
or
irritation involved. This just looks like bits of the fin are
disappearing.
Is that still fin rot? And if so, what's the best treatment?
Finally, should treatment be conducted apart from the other fish in the
tank, ie, should I try to quarentine this one, or will the others be
okay
with the added medication?
TIA

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