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.