How to Remove Cloudy Water From a Saltwater Aquarium

Written by williamd
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How to Remove Cloudy Water From a Saltwater Aquarium
A saltwater aquarium that is maintained is a wondrous centrepiece in any room. (aquarium fish 9 image by cherie from

Cloudy water can be a problem for a saltwater aquarium, leaving the water murky and the fish difficult to see. If left unchecked it can get worse and spread disease, particularly if it is related to bacterial issues. A variety of situations can create cloudy water, and the first step is to identify the cause. Fortunately, there are solutions to prevent it from recurring. A healthy aquarium is full of clear, clean water, vegetation and fish.

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Things you need

  • Siphon
  • Gravel Vacuum
  • Saltwater aquarium filter

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  1. 1

    Find the cause of the problem. If you filled the tank with water, laid down new gravel and the water is cloudy, it's possible that the gravel wasn't properly rinsed before being placed in the aquarium and that phosphates and residue are present.

  2. 2

    Empty water from the aquarium and remove the gravel. Wash it thoroughly, without soaps or detergents, rinsing it until the water is clear. Do this in a large dish or bucket so you can run water over it to wash it well.

  3. 3

    Place gravel back in the aquarium and fill it up with saltwater. The water should stay clear.

  1. 1

    Check your water filteration system if your aquarium water begins to get cloudy. If it is malfunctioning or blocked to the point where it isn't filtering the water properly, there's a chance that the water is polluted with bacteria from rotting food and debris. Switch the system off before checking it. If you suspect this might be the problem and you can't repair it, replace the filter.

  2. 2

    Remove the fish from the aquarium if the problem is caused by a faulty filtration system. Place the fish in a clean, temporary tank until you can repair or replace the filter.

  3. 3

    Replace or repair the filtration system, first removing all ornaments, plants and gravel. Do this after the fish have been removed. Place the plants in a container with saltwater added.

  4. 4

    Clean the aquarium, gravel and ornaments.

  5. 5

    Put the new or repaired filtration system back in the tank, and add the gravel, ornaments and plants. Run the filter for at least 24 hours, and once the ideal water temperature is reached and everything is set up, add the fish.

  6. 6

    Siphon or vacuum the tank once or twice a week to remove food particles and debris from the bottom. Buy a gravel vacuum or siphons from aquarium suppliers or pet stores.

Tips and warnings

  • Overfeeding creates cloudy water.
  • Check the filtration system regularly and monitor any changes in water clarity. Check water pH levels. High alkalinity causes cloudiness.
  • Remove decaying plants and dead fish.
  • If the filter is working well and the aquarium is kept clean, the water will clear up as bacterial levels balance out. This may take weeks or months.
  • Add water conditioners to remove cloudiness caused by dissolved constituents from the gravel. Buy these at an aquarium fish store.
  • Buy water clarifiers if you are unable to remove all the debris in the tank.
  • Do not change the pH level of your water until you determine what is ideal for the species of fish in the tank.

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