About Chloramine

Chloramine is a chemical used to disinfect water. It is ammonia (NH3) bonded to chlorine. It resists breaking down and is used because of its stability in water. Many commercial chlorine removers can be used to remove the chlorine, but when used alone, ammonia is left over. The toxicity of ammonia will depend on a few factors. This article should help you decide the best course of action in your situation. Ammonia is not toxic at a pH below 7.0. This happens because, in acid conditions, free hydrogen ions convert it to ammonium NH4. As pH rises above 7.0, these hydrogen ions are less available, leaving more toxic ammonia (NH3).

Chloramine Removal

Chloramine can be removed in several ways. You can purchase a product like No-Ammonia, but it can be fairly expensive if you are dealing with a large hatchery and frequent, large water changes. No-Ammonia creates a chemical bond with ammonia that is synthesized by nitrifying bacteria. Items like Zeolite will also remove ammonia, but its effectiveness is limited and not the best solution in most situations. You can also remove the chlorine with very inexpensive sodium thiosulfate and deal with the ammonia separately.

Removing Ammonia Separately

If you decide to use sodium thiosulfate to remove the chlorine and deal with ammonia on its own, then the following will explain what to try. Nitrifying bacteria will convert ammonia to non-toxic ammonium. If your biological filter is a good one and the fish load is not too high for the filter, it may be all you need. Its effectiveness will vary depending on pH and fish load. To find out if your filter can handle the ammonia load, get a good ammonia test kit, do small water changes and carefully observe what happens. Start out with 5% water changes and increase them 5% at a time, until you see that the ammonia level is stressing the fish. At the level you can observe stress, you should cut back about 10% on the amount of water changed. With this method, you will probably never be able to do more than 30-40% water changes. If you’re restricted to a small percentage, then you will have to do water changes more frequently than you would otherwise.

If stress is seen at all levels, you will have to increase your aeration and biological filtration or resort to chemical removal of ammonia. The best course of action to remove ammonia will depend on your water’s pH, the amount of ammonia in the water, the fish load and the size and efficiency of your biological filter. Most situations can be handled with sodium thiosulfate and separate ammonia removal. You can decrease fish loads, increase biological filtration and even go so far as to lower pH. Some go through the effort of adding large amounts of reverse osmosis water to lower pH. You can also increase filter efficiency by installing oversized, high flow rate trickle filters that expose water for optimum gas exchange and biological filtration. It’s worth doing all this, not only to avoid chemical removal of ammonia but because it generally provides better conditions for your fish. This results in faster growth, more color and more beautiful fish.

If you get your aquarium water from a commercial water system (tap water), that water is treated to make sure it’s safe for human consumption. The water is cleaned and filtered. Chemicals are then added to the water to prevent anything harmful from growing in the water while it’s in the pipe leading to your home. Until recently, most water treatment facilities used chlorine to kill off any organisms in the water. This small dose of chlorine is safe for human consumption.

The problem water treatment facilities have with chlorine is that it’s unstable and easily dissipates from the water. This means that the treatment plants need to put in higher levels of chlorine so that they can be sure that some will remain in the water when it reaches your home. Recently, water treatment plants have started treating tap water with chloramine instead of chlorine. Chloramine is a combination of chlorine and ammonia. It’s much more stable than chlorine, does not dissipate from the water as easily, and it isn’t as likely to combine with other chemicals. But chloramine isn’t as good at killing off the microorganisms in the water as chlorine, so higher levels of chloramine are often used. Typically, water treatment plants use about 1 ppm of chloramine.

Adding chlorine and chloramines to our drinking water is very important to keep people healthy. But the same chemicals which keep us safe can be very toxic to fish. Adding tap water with chlorine or chloramine to a tank can quickly kill off fish. It can also kill off the nitrifying bacteria that keep your tank stable and healthy. So, it is important to remove chlorine and chloramines from your aquarium water. There are several common approaches, and their effectiveness varies depending on whether your local water treatment plant uses chlorine or chloramine. If you don’t know which your water system uses, contact them and ask.

The simplest and most effective way to remove chlorine and chloramines from your water is using chemical dechlorinators. There are many products sold for aquarium use that are specifically intended to remove chlorine. FritzGuard® and Fritz Pro Concentrated Chlorine Remover are two of these. They both include sodium thiosulfate, which reacts with the chlorine (or the chlorine portion of the chloramine) to form harmless chloride ions. The chlorine is completely and totally removed. This reaction happens instantly. The tap water doesn’t need to be mixed with the dechlorinator for any amount of time before adding it to the tank. It’s safe to just add the dechlorinator as you add the water into the tank.

There is one potential problem if your water is treated with chloramine. As stated above, the dechlorinator reacts with the chlorine portion of the chloramine. The chlorine is eliminated, leaving the ammonia free in the water. As you hopefully know, ammonia is toxic to fish, even at low levels. So, if you use a simple dechlorinator that only contains sodium thiosulfate, you are solving one problem (chlorine) and creating a new problem (ammonia).  Fritz offers two products that detoxify ammonia: Fritz A.C.C.R. and Fritz Complete Water Conditioner.

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