How to Clear Cloudy Water in a Brackish Water Aquarium

Fish tank water can become cloudy for a number of reasons, including debris from the substrate you use, bacterial growth, chemical imbalances and algae growth. Regardless of what causes the cloudy appearance, it is unattractive and in some instances can pose a danger to the health of your fish. Although the appearance of cloudy water can be off-putting, if you have a brackish aquarium -- one with a mix of salt water and fresh water -- clearing your water requires just a few steps.

Things You'll Need

  • Water quality testing kit
  • Water conditioners
  • Siphon
  • Fish tank filter
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Instructions

    • 1

      Check the water using a store-bought water quality testing kit. The ammonia, pH, chlorine levels and salinity depend on the type of aquarium you have and the types of fish you are keeping. Follow the instructions in the testing kit to determine proper testing procedures and what is appropriate for your tank.

    • 2

      Add water conditioners based on the results from Step 1. The type of conditioner to use depends on which water quality level was off. Follow the package directions for appropriate application methods. Depending on your test results, you may also need to add aquarium salt. Follow the package directions for the correct adding and dosing procedure for your specific tank and test results.

    • 3

      Remove the fish tank filter and clean it under running water. Inspect it for any tears or perforations in the mesh cover. If the filter is damaged, discard it and replace it with a fresh one. If you find a buildup of grime on the mesh cover, install a fresh filter. A dirty filter that cannot properly do its job can lower the water quality.

    • 4

      Siphon the bottom of the tank, cleaning the substrate, live rocks and other tank decorations.

    • 5

      Perform a daily 20 percent water change, advises the AquariumFish website. Once every day, until the problem is resolved, remove 20 percent of the tank's water using a siphon or a bucket. Replace it with the same amount of fresh, clean water with salt mix added in. Do not change more than 20 percent of the water at a time or this could shock your fish, resulting in harm.

    • 6

      Avoid overfeeding your fish. Feed them only what they can consume in 10 minutes. If food remains after 10 minutes, use a net to remove it.