How to Clear up Cloudy Fish Tanks

With cloudy fish tanks, there is no one solution to the problem, because there is no single definite cause. You must examine the color and recent changes in your tank to determine the best course of action. Sometimes you just need to wait out the murkiness, while other times you should react immediately. As you grow more experienced keeping fish tanks, you'll learn how to fix the problems.

Things You'll Need

  • Testing kit
  • Ammonia drops
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Instructions

    • 1

      Wait for the water to settle. If you recently changed the water, added something new to the tank or have a new set-up, then cloudy water is normal as the dirt in the gravel kicks up. Wait about 24 hours to see whether it clears up.

    • 2

      Remove and rinse gravel if the cloudiness appear immediately or within a hour of filling the tank. This will cut down on the dust released into the tank.

    • 3

      Clean your filter and pump. Replace old cartridges. Then give your tank about 6 hours to clear up. If the water is still cloudy, you should look for other causes.

    • 4

      Use a master test kit to measure your aquarium's pH, ammonia, nitrite and nitrate levels. This kit can be picked up at most pet stores and helps you decipher what is going on in your tank.

    • 5

      Adjust nitrate and ammonia levels. There are tests you can perform to test this, or you can simply replace about 20 percent of the water and see whether that helps clear up the water.

    • 6

      Add ammonia or nitrate drops to the water. Sometimes adding drops (or packaged good bacteria) can simply hide a problem without fixing it. The drops, which can be purchased at any pet store, offer an immediate solution. Be sure to follow the package's directions, so you do not poison the fish.

    • 7

      Let your filter clean brownish or yellow-tinted water, which may occur when gravel with too much organic matter is disturbed. Add a carbon additive to reduce it.

    • 8

      Stop overfeeding if your water starts to turn green and murky. This is caused by algae, which grow due to excessive feeding and abundant light. Changing the water won't help as the spores remain in the tank. Vacuum the gravel, rinse the filters and add as much oxygen as possible to the tank while you wait for the algae to clear up.

    • 9

      Introduce Copepod and Amphipod-eating fish to the tank. The striped Mandarinfish and Gobies eat these tiny bugs, which cause very white cloudy water in saltwater tanks.