How to Change & Dechlorinate Aquarium Water

Regularly changing and dechlorinating aquarium water keeps your fish healthy. These essential maintenance tasks ensure the water is clean and free of impurities, and dechlorinating water is less scientific and less complicated than it sounds. Purchase a water conditioning product from a pet supply store, and when you are replenishing the water, add a little of it to the fresh water supply. It̵7;s also important to remove impurities from gravel at the base of the tank when you are replacing the water. An effective way to do this is to remove the dirty water with a siphon that is also designed to clean gravel.

Things You'll Need

  • Water conditioner
  • Gravel cleaning siphon
  • Clean 5-gallon bucket
  • Damp sponge
  • Algae scraper
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Instructions

  1. Dechlorinating

    • 1

      Select a dechlorinating water conditioner that is suitable for your aquarium, depending on whether your have a salt-water or fresh-water aquarium. Some water conditioners are suitable for both.

    • 2

      Follow the manufacturer̵7;s instructions carefully. You usually need to add 1 or 2 drops of the liquid solution per gallon of water.

    • 3

      Add the freshly-treated water to your aquarium when the chlorine and chloramines have been removed. The cleansing process usually takes around five minutes, but refer to the manufacturer̵7;s instructions for the specific conditioner you are using. It̵7;s only necessary to dechlorinate water that is being added to the tank.

    Changing the Water

    • 4

      Remove 10 to 14 percent of the aquarium water with siphon. Transfer the dirty water to a clean 5-gallon bucket. Don̵7;t remove all the water from the tank because this will remove healthy bacteria.

    • 5

      Dispose of the dirty water and rinse the bucket thoroughly, but don̵7;t use soap or detergents.

    • 6

      Pour fresh water into the bucket. The temperature of the replacement and existing aquarium water should be the same. Test the water temperature of both with your fingers, adding warm or cool water as needed. Dechlorinate the water after you get the temperature right because hot water contains more contaminants.

    • 7

      Wipe off any algae that has built up on the surface of the glass with a clean, damp sponge or an algae scraper, available from pet stores.

    • 8

      Siphon the clean water into the aquarium, ensuring that you leave a space between the water̵7;s surface and the tank cover to give the fish the oxygen they need.