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What Causes Cloudy Water In My Aquarium?


The article concerns the following question – What Causes Cloudy Water In My Aquarium? This is one of the most perplexing problems we encounter with the aquarium hobby.  We can usually pinpoint the problem based on the color of the water.  Just remember – Don’t panic.  We all have gone through this from time to time and you just need to use some common sense concerning the cause, how to correct it and how to prevent its return.

What Causes Cloudy Water In My Aquarium

White or Grayish Water

If you have just set up your aquarium this might be caused by unwashed gravel or substrate.  Make sure you always wash your substrates before adding it to your aquarium.  You could either drain the aquarium and wash the substrate or it will correct itself eventually through filtration.

High pH or Phosphates in the newly added water.  You need to always test new water for high alkaline content.

If the cloudy water occurs weeks or months after setting up the aquarium, it is probably due to a Bacterial Bloom.  Your aquarium may not be established with the Nitrogen Cycle.  Bacteria need time to grow to clear up the wastes.  Decaying food and plants will cause the imbalance in the cycle.  Cut back on the feeding as you may be overfeeding allowing a lot of food to drop to the bottom of your tank and decaying.    Make sure your filter is clean, do a partial water change, clean the gravel and the situation should right itself.  When cleaning your filter, remember to rinse the filter in aquarium water and not tap water.  You do not want to disturb the beneficial bacteria that has already grown.

Overcrowding of fish can also cause a Bacterial Bloom as the filtration system cannot keep up with the fish waste.

If after trying all of the above (partial water changes, cleaning the filter and substrates) you might want to try a Flocculent (water clarifier).  Flocculents cause the debris to clump together so they can be filtered out.

Green Water

This one is pretty easy to identify.  It is excessive algae causing the water to have a greenish color.

Excessive algae is usually due to a light problem.  Move your aquarium away from windows and direct sunlight.  Too much light causes algae to grow.  You might also want to limit the amount of time you keep your aquarium lighting on.

Another cause is a rise in nitrates and/or phosphates which is a direct result of overfeeding, rotting food and plants and infrequent water changes.

To solve your green water problem, you will need to do water changes, eliminate the light source that is causing the algae to grow, and clean your filter.  You can also add a water treatment like Algone to help clear up your water.  Also reduce feeding, as the phosphates are a direct result of rotting food that is not being eaten.  Nitrates are a result of fish wastes, so make sure your aquarium filter is doing its job of removing the debris before it has a chance to cause problems.

Yellow or Brown Tint to the Water

This problem is associated with the activated carbon if you are using it.  If you don’t use it, you might want to try adding some to alleviate the problem.

Water problems can be so very frustrating, but in order to maintain a healthy aquarium, there is work involved.  Water changes are so very important as well as keeping the aquarium clean the the aquarium filter in good working condition.  The rewards are great after the work is all done and you can sit back and enjoy the beautiful underwater world you have created!

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