"Lucky" wrote in message
ups.com...
Two of my little fish died in the last week, about 4 days apart. Before
they dies they were bent in 'u' shapes and then they just skulked away
to die. They looked like they had 'internal bleeding' if that makes
sense. One of he fish was spending a lot of time on the bottom of the
tank before it got really sick, so i medicated the tank. That didnt
help though. The other fish died suddenly. Does anyone have any idea
what that could be and what would have caused it? More important to
know what would have caused it so I can prevent it again.

My other main question is about my remaining fish. It seems fine and
healthy now but I'm worried it will die the same way as the other
two... do parasites live in the water? I just dont know what to do
about the water because obviously i don't want to put compltely new
water in the tank, but i don't know if there is some 'disease' in the
water? So i am reluctant to put any new fish in there as well...

All advice would be appreciated.

If it was parasites that killed your fish, then yes they could still be
present in the water. However if your remaining fish are 100% healthy then
the chance of the parasites being able to infect your fish are greatly
reduced. Many common parasites only infect fish that are stressed and
unhealthy anyway. Remove any unhealthy fish to a hospital tank, as soon as
you spot them, to protect the remaining fish.

You need to take great care of your remaining fish, doing minor water
changes frequently and ensuring they remain in peek condition. Over time any
remaining parasites will perish without a suitable host fish. You are
correct in saying that a 100% water change will probably stress your fish
more so then maintaining them in the current water. Stressed fish would
become susceptible to further parasitic infections. (you could never
eradicate all the parasites with a total water change anyway).

If you want to spend some money on this problem, then get a UV filter. This
will kill all parasites as they pass through the filter. Not a cheap
solution though.

**SS**