Tap Water Conditioning and Treatment

There are two things you should do when performing regular maintenance water changes for your fish: correct the temperature, and remove the substances which are toxins to your fish. If you use bottled water, you only need to worry about the temperature. You should never, ever use distilled water, as it lacks nutrients vital to the health of fish. But any other spring or bottled water is usually fine (I say usually, as it may not contain enough of a buffering capacity, and you will notice that levels fluxuate). Water from a well may not require additional maintenance at all, but since most of us use good ole' plain tap water for our fish, we have to do a little maintenance to the water before using it:

1) Allow your water to become the same temp as the fish's existing water to prevent temperature shock to the fish, which will leave it vulnerable to a number of parasites and bacteria. Sit tap water out overnight before using it so that it'll be room temperature. If your fish is in warmer water, you should get the water warm to the same degree, only varying a degree or two, before putting your fish in it.

Regardless of whether your municipality's water system uses chlorine or chloramine, these chemicals eventually break down. Chloramines are a more stable compound to begin with, so they remain in the water a little longer that chlorines do. But simply waiting for these chemicals to evaporate from your water is not usually good enough: metals found in tap water will not chelate on their own. Most any city's tap water is going to have some heavy metals, simply due to the pipes the water is carried in, especially if they are older pipes. This is why we use:

2) Tap water conditioner: to quickly and effectively remove water treatment, and any possible heavy metals. This is a safe and necessary practice fishkeepers need to become quite familiar with.


But Wait! There's More!

Sorry, you probably thought you were in the clear already. :> But, there's one more important thing you should know. Chlorine (chloride and water) or chloramine (nitrogen gas, water, and HCl) will react with tap water conditioners to form simpler, more stable compounds. If your city's water is treated with chloramine, conditioning the water will break down and release ammonia into your water. You must also treat for this, else you'll be introducing even more toxins into your fish water.

In plain English: some tap water conditioning products will note on the label that they also treat ammonia. If your city water is treated with chloramine, use these. If you don't know, test your water for ammonia after dechlorinating it!