Sounds like swimming bladder infection - fantails seem to be prone to this,
especially the ones that are really wide at the front part of their body - I
was able to treat a couple of mine in a "hospital" tank , but it always came
back www.koivet.com is a good source for reference
Gale :~)
" a friend's fantails seem to keep coming up to the surface whether they
want
to or not. One has died already and the other though it looks fine is not
acting right. It basically seems to not be able to keep itself in a
normal
position... Any ideas?