Why is my Fish Tank Water Cloudy?

If you are struggling with a cloudy fish tank, whether you have cloudy water in a new fish tank or cloudy water in an established tank, we have a few ideas on what causes cloudy aquarium water and how to fix a cloudy fish tank to ensure your tank is back up to scratch in no time at all.

Why is my Fish Tank Water Cloudy?

There are a number of reasons why you might be suffering from a cloud aquarium, these range from bacterial blooms after a water change to a range of other contributing factors. When looking at why your fish tank water is cloudy it is important to distinguish between cloudy water in a new fish tank and cloudy fish tank water in an established tank in order to dictate the next steps you need to take.

What Causes Cloudy Water in a New Fish Tank?

If you are struggling with cloudy water in a new fish tank, the good news is that this is not unusual at all. New fish tanks don’t yet have an established biological state. This means that there are all sorts of microscopic organisms in there trying to establish themselves before the nitrifying bacteria that filter the water kick in. This can easily cause cloudy water in a new fish tank, particularly if a lot of new fish and their food supply are added at once, as often happens with a new tank.

In this case, the best option is often to do nothing. During the first few weeks of your fish tank, the water will naturally be a bit cloudy whilst everything adjusts, so it is worth allowing your new fish tank time to acclimatise. Doing this gives the good bacteria in your fish tank time to establish itself without constantly being renewed by water changes and creates a healthy, stable environment for your fish to live in.

How Can I Prevent Cloudy Water in a New Fish Tank?

Whilst your new fish tank will take some time to establish itself, there are a few things you can do to help it on its way and avoid cloudy water in a new fish tank. These also work as a general rule for avoiding cloudy water in an established fish tank.

One of the first rules to avoid cloudy fish tank water is to avoid overfeeding your fish. When you over feed your fish, the food then breaks down and feeds the bacteria contributing to your cloudy fish tank water. Uneaten fish tank food can also cause an increase in ammonia and nitrate which are harmful to fish so best avoided. You should also avoid putting too many fish in your new fish tank at once to again avoid waste.

Some other cloudy fish tank solutions include seeding your new aquarium with gravel, and therefore bacteria, from an already established tank to help the good bacteria in your new tank thrive. You can also add an activated carbon filter to your fish tank to help clear your tank water and absorb other nutrients that may feed the bacteria bloom in your new fish tank. Testing for ammonia and nitrate regularly will also help keep your fish tank healthy.

Fixing Cloudy Fish Tank Water in an Established Tank

Whilst cloudy water in a new fish tank is not usually a cause for concern, cloudy fish tank water in an established tank is something that should be addressed. If you are battling with cloudy fish tank water in an established tank then this could be caused by a bacterial bloom which can go away on its own after your tank cycles itself. If you are looking for a way to combat this however, there are a few things you can try.

The first step in avoiding cloudy fish tank water in an established tank is to ensure you regularly maintain your fish tank filters to top working condition. You should regularly clean your fish tank filter to avoid a cloudy fish tank. However, whilst you should change around 25% of your fish tank’s water a month, changing the water too much can also lead your fish tank to start cycling again. This is because it will need to start establishing a working biological state from scratch. This will inevitably cause cloudy fish tank water whilst the good bacteria in your tank reestablishes itself. 

If you are worried about cloudy fish tank water, aquarium upkeep or have any other questions, get in touch with our expert team online or by calling 01922 416284. We also provide a range of aquarium supplies for every type of aquarium online, see the collection here.