What Does Conditioner Do for an Aquarium?

A water conditioner untreats your treated tap water.
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If you've done your homework on maintaining an aquarium for your finned friends, you've figured out you need to add water conditioner to the tank. And now, you want to know why. Conditioner makes your chemically treated tap water safe for your little fish to swim and breathe in.


Not to gross you out, but your tap water is treated with chlorine or, more likely, chloramine, which is a chemically bonded combination of chlorine and ammonia. As unappetizing as they may sound, these treatments keep bacteria and other undesirable microorganisms out of your water so it's safe to ingest and clean yourself with. At the levels used, these treatments pose no threats to human folk like yourself, or even to any of your fellow mammals or other land-dwelling critters. But -- and this is a big but -- the levels are high enough to cause toxicity in fish and to seriously interfere with many aquarium filtration systems.


Once people figured out why their marine companions kept dying off, the solution was pretty simple: use conditioners that eliminate or render inert the offending chemicals -- the chlorine and ammonia. Three main water conditioner classes are made. The most basic are dechlorinators. In a matter of minutes, it gets rid of chlorine, but only chlorine. Then there are chloramine neutralizers. These conditioners take care of the chlorine and the ammonia in your water, and some even detoxify heavy metals. Finally, there are complete conditioners. These dissipate the chlorine, neutralize the ammonia, handle the heavy metals and clear out the copper.


The various types and brands of water conditioners have slightly varying instructions. So, before you use any for your water-bound buddies, read all the manufacturer directions and warnings. Dosages of one to two drops per gallon are fairly standard, but again, always go with what the package says. Once your aquarium habitat is initially treated, you'll only need to treat new water added during partial water changes. A bucket's worth of water is generally dechlorinated within about two minutes and dechloraminated within about five minutes.

"Specialty" Conditioners

Most water conditioners are relatively cheap; usually you can spend a few bucks and be set on conditioner for a year. But the entrepreneurs out there are always looking for ways to squeeze a little more out of you. The market has plenty of "specialty" conditioners that do all sorts of extra stuff for your aquarium. Different products allegedly reduce stress in your fish, indulge them with spa-like scales treatments, soothe them with aloe and vitamin E and so on, and so forth. Mostly, these are entirely unnecessary excuses for charging you more. Along with raising your cost of basic aquarium care, these extra ingredients provide more opportunity for the product to interfere with your filtration system or tip your water chemistry out of whack.

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