"fish lover" wrote in message
...
On Tue, 13 Sep 2005 14:47:12 +0100, Neil Woodman
wrote:

Graham Ramsay wrote:

"Neil Woodman" wrote
There seems to be nothing wrong with the filter but the water has gone
really cloudy, I have 4 fish left which are still alive but my shrimp
are
perched on top of the inside edge of the tank, literally out of the
water!
They don't look too happy either.

I have always done large water changes as I do about 30% per week, is
this
wrong?




It does sound like your filter has died off for some reason.
Do you have high nitrite or ammonia levels?
30% weekly is fine.

--
Graham Ramsay
Fair City Aquarist Society




What I think is that when I filled my filter cannister up, (its
external) I used fresh water from the tap which I did dechlorinate but
maybe that has killed off the bacteria in the filter and caused it to go
anerobic, that would explain the suddenly oxygen drop and the dead fish.
Normally I just tend to let water into it by the inlet pipe as there is
a syphon action going on with the external filter but I didn't do this
when I last did the water change.

Filling the filter with tab water will kill everything in it. That for
sure will cause your tank water go bad. You need to add something to
help it cycle again. AND to put something to remove the amo right now!
Otherwise all you fish will die

Why would *dechlorinated* tap water kill "everything"?
I use dechlorinated (actually dechloramineinated ...
probably not a word... g) tap water all the tap in my
tanks. What else would you fill the tanks up with when
topping off??

One possibility is that the OP's water system might
have changed from chlorine to chloramines. That
can be deadly to fish if you're only treating for
chlorine. It might be worth a call to his local
water utility.

Gail
Southcentral TX USA