What happens to tap water when it is aged?

[bossteck]

Can someone tell me what happens to tap water when it is aged?

My understanding is that chloromaine does not get dissipated that easily, so strictly speaking aging does not help in removing it. Chlorine on the other hand, does, enough surface agitation provided by an air pump, one can get rid of chlorine in the water.

So what else happens to the water when it is age?

My personal practice is, always do small amount water changes (about 10&#37 and add water conditioner.

[benny]

I believe in the old days, before the use of Chloramine, it ws sufficient to just let the water sit for a day or two before adding it to your aquarium. Free chlorine would dissipates pretty rapidly into the atmosphere and the aged water would be safe enough for aquarium use.

You are right that Chloramine does not get dissipated easily. In fact, it is such a stable compound that it does not break down naturally. Chloramine (NH2Cl) combines ammonia with chlorine, which gives it the advantage of being more stable than chlorine by itself. Obviously, to us, ammonia is also very toxic to fish. This means that we NOW need to treat the Singapore tap water for both chlorine and ammonia before adding it to the tank.

From what I heard, when we age the water, micro bacteria also forms in the water. I don't know how true this is, but the experiment I was told to do was that when we leave a tank of water unattended, the sides of the tank will have a thin layer of slipery film. That's suppose to be a layer of bacteria. Perhaps somebody more knowledgable can verify.

Cheers,

[PeterGwee]

Bacteria will grow once the chloramine concentration goes down over time. Aging the water merely grows bacteria, fungi and etc. If you do frequent large water changes with dechlorinator / anti-chloramine, things will be fine but not when you don't and suddenly do one. The issue is not with the large water change but the amount of salt content difference between the tap and the tank water. That is what kills fish/critters....add lots of baking soda to the tank suddenly and you will kill fish/critters. You can get over that issue with a slow water change (sort of like the drip method but probably not that slow.)

Regards,
Peter Gwee

[bossteck]

Hi guys,

Thanks for splitting the discussion and clearing that up.

[DazzleDiscus]

Don't know how this fits in exactly, but whenever I do a water change and don't let my refill water sit for about 20min my guppies stay at the surface lathargic-like. When I let the water sit for a bit they're fine. none of the other fish are affected. My mom suggested that it could be our filtering system (we have well water) Didn't quite understand/listen all the way- but for some reason we have something that injects a high-powered stream of air into the water to get rid of excess iron. She said they might have acted that way because the oxygen levels were too high... somehow that just doesn't sound right, but then again I wasn't very good as chemistry stuff. Anyway... Could the change in oxygen levels affect the fish so that they act like they're shocked? No other bodily signs- no reddening of the gills or anything.