PlanetCatfish.com

Hi, I was wondering if anyone knows of any information regarding this common water treatment and potental hazards/effects upon our aquariums. It is widley used but there is little to no info regarding it in the context of tropical fishkeeping. The reason I was seeking the info was because of some recent fish kills in several tanks. No water parameters were out or abnormal but when checking with my local water company site I noticed this chemicle was being added at a higher rate than usual. The only casualties were 100% of my pim pictus, guppies and yoyo's, only symptoms were a slight breathing problem (fast). Species such as betta, Gibby, Ancistrus, clown loach, swordtail, synodontis N and U, several barbs and rainbowfish sp. were completley unaffected. because of the 100% of some species, 0% of others I am suspecting a contaminant.

What is the pH of your water? Aluminium has been shown to be a pH-dependent toxin in some fish.

What area are you in, Azmeaiel?

Because of the drought, Melbournes water supply is way down. Tap water has dropped to pH 6.7.

Have you confirmed any losses at the Aquarium Outlets?

The ph of our water is usually a constant 7.2-7.5 ph. I forgot to mention that our local LPS has a similar problem with the same species of fish, usually over the summer period. I have been talking to a few lps and they cannot keep guppies at all, some have obviousley stressed fish with bad columnaris outbreak. Breeders in melbourne are also reporting a similar problem but no-one can pin the cause as all water test read normal as far as ammonia, nitrite, nitrate and ph are concerned. The only link is the fact that it is summer and water levels are low and there is increased treatment of local water supplys.

fish that are noticed early and are removed to an aged tank (with no water changes for a while) will usually quickly recover. symptoms are red gills, gasping at surface (or just rapid gill movement in catfish). In very bad cases the fish will stop eating for 1-2 weeks and on occasion develop columnaris (especially in the case of guppies). All the sumptoms of severe nitrite poisoning but with no nitrite present at all. In case of the botia and pictus (all except for one that was removed)they just turn up dead within hours of a water change. tests on tapwater reveal nothing more than unusually high chlorine ( 0.77). Is there any possible harmful residue of chlorine removal?. This one has a lot of people over here totally stumped. Some even resorting to no water changes for 3 months over the summer period.

any info of aluminium sulphate and PH tocicity would be of great help.

Aluminium only becomes really toxic when the water is very soft and acidic, so from the values you give, it may not be the responsible agent.