How to lower ammonia levels

Written by lee buchanan
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How to lower ammonia levels

Ammonia is one of the most lethal water conditions in both freshwater and marine aquariums. Fish, in particular, are vulnerable to high ammonia levels, which will either kill them outright or stress them so badly that they become much more prone to disease.

Skill level:

Things you need

  • Aquarium
  • Ammonia test kit
  • Distilled or reverse-osmosis fresh water

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    Emergency measures

  1. 1

    Test the water for ammonia. Established tanks should register zero ammonia. A level of 1 ppm or greater demands immediate action.

  2. 2

    Conduct a critter count. Account for all your tank's inhabitants to make sure something hasn't died. The most likely suspect in an ammonia spike--other than overfeeding--is the presence of a decaying animal. If you find a carcase, remove it.

  3. 3

    Use an ammonia-remover additive to reduce ammonia immediately if your fish appear severely stressed--gasping for air near the surface or lying on the sand bed. This is only a stopgap measure, but it may save your fish while you work to reduce ammonia levels permanently.

  4. 4

    Stop feeding until you bring down the ammonia level. Don't worry: Missing a few meals won't harm your fish.

  5. 5

    Do a partial water change. Aquarium hobbyists have a favourite saying that covers many aspects of successful aquarium-keeping, including ammonia poisoning: "The solution to pollution is dilution." Change 30 per cent-40 per cent of the water, using distilled water or reverse osmosis water (preferred) from an aquarium store. Of course, if it's A marine aquarium you'll need to prepare salt water at the same salinity as your tank water. For both freshwater and marine tanks, bring the water up to the same temperature as your tank water.

  6. 6

    Wait a day and test again for ammonia. If it's still at 1 ppm or above, do another water change, changing slightly less water than the previous change. If you changed 40 per cent the first time, make it 30 per cent for the second change. A series of water changes may be required.

    Long-term solutions

  1. 1

    Keep ammonia at bay with regular maintenance. Ammonia levels should never be above a trace in an established tank. Test regularly.

  2. 2

    Keep track of your tank's inhabitants. When something dies, remove it immediately.

  3. 3

    Do not overfeed. This is the cardinal sin of aquarium keeping. Uneaten food decays and will cause the dangerous cycle of ammonia, nitrites and nitrates. Waste also contributes to this cycle, and more food equals more waste. A good rule of thumb is to feed only an amount that is consumed within five minutes.

  4. 4

    Remove dying plants. These, too, contribute to a rise in ammonia.

  5. 5

    Clean the tank regularly, especially by vacuuming the gravel or sand bed.

Tips and warnings

  • Monitor PH while you're working to lower ammonia. Rising levels of ammonia will cause PH to drop. Since higher PH makes ammonia even more toxic to fish, don't raise PH until the ammonia crisis is resolved.

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