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How to Keep Algae Out of a Fish Tank

how to keep algae out of a fish tank

Algae growth is an aspect that every fish tank owner will have to deal with anytime. The maintenance process of an aquarium includes dealing with different types of algae and their possible effects on the fish. However, please note that having algae growth in your fish tank is not necessarily bad after all. It is a part of nature that shows that your fish tank is healthy and well-balanced.

But how to keep algae out of a fish tank? Only when the algae grow out of control and start covering all the parts of your fish tank that it can be hazardous to the fish and the tank. Once left unchecked, it can grow on the aquarium rocks, tank decorations, aquarium plants, and many more crucial parts of the fish tank. However, there are many ways to reduce and even eliminate this overgrowth of algae and possibly reverse its effects.


Eliminating Algae Overgrowth in Fish Tank

As they say, prevention is better than cure. And there are different ways to keep the overgrowth of algae in the fish tank. If you know what causes the overgrowth of algae, then it will be a great advantage to you. You can also eliminate algae overgrowth by doing the following steps below:

Lighting Reduction

Exposure to sunlight is a significant contributor to algae growth. So, it is essential not to position your fish tank directly to the sunlight during the day because it can promote algae overgrowth. Another alternative is to use artificial light, but the exposure should be limited to 8 to 10 hours per day.

Changing Aquarium Water

One of the best ways to keep the algae out of the fish tank regularly changes the water content. It does not need to be a complete changing of water, but replacing around 10 to 25 percent of water content weekly can help keep the algae from growing. Doing this will help maintain the nutrients low while removing the nitrates inside the fish tank, preventing the algae from growing.

Testing the Water Source

It is essential to test your water source if it is in high phosphate and even elevated nitrates. All of these minerals can help in overgrowing algae in your fish thank. You can use phosphate removing chemicals or might change your water source to prevent problems in the future. As for the nitrate levels, it does not look good if you change the water if you are adding nutrients in the tank by adding tap water.

Reduce Fish Feeding

Most fish tank owners have this common mistake of overfeeding the fish, which contributes to increasing the phosphate levels of water. You will only need to feed small portions to the fish to prevent overfeeding. If you happen to see uneaten foods, you can immediately remove them because failure to do so might accumulate at the bottom at helps algae growth.

Keeping Live Plants and Algae-Eating Fish

If you have live plants in your fish tank, they can absorb all the nutrients that help the algae grow. These plants will make the nutrients lesser on the tank, which means fewer chances of the algae to grow. Meanwhile, algae-eating fish such as plecostomus and flying fox can help reduce the algae in the tank.

Cleaning it Up

If you are beginning to see algae growing on different parts of the fish tank, then you must clean it at all costs. Remove rocks and scrub them, or you can scrape the glass. You can also vacuum the gravel when doing a water change.

how to get algae off fish tank decorations

How to Get Algae Off Aquarium Rocks

Removing algae off the aquarium rock only needs a straightforward process. But you will need to remove other parts during the cleaning, such as the decorations and the plants. You also need to remove it slowly not to stress the fish. Then, you will need to remove the rock away from the tank and place it in hot water that should reach boiling point. Soaking the rocks for 20 minutes can kill a lot of algae.

You can also get a new toothbrush and scrub the rocks thoroughly to remove the algae. But you need to be gentle by cleaning every surface of the rocks to eliminate the algae. You can also create a 5% bleach and 95% warm water bleach solution and soak the rocks again. Use the toothbrush to scrub the rocks again. After cleaning, rinse the decorations thoroughly with cold and warm water alternatively to altogether remove the chemicals. Then, you can put the rocks again in the tank.

How to Get Algae Off Fish Tank Decorations

When it comes to cleaning the tank decorations, you do not need to remove everything in one setting. Do it gradually, probably 25% to 50% at a time during the cleaning process. Failure to do these may upset the fish and might create an imbalance of the aquarium environment. So, you can divide the decorations into half or more or clean them in groups.

Follow the same procedure as cleaning the rocks by using boiled water in 20 minutes. This action will kill a lot of algae in the process. If you have more stubborn algae on the decorations, you can use the bleach solution to remove the algae while also used the toothbrush to scrub it. Do not forget to rinse the decorations with water before installing them back in the tank.

How to Get Algae Off Aquarium Plants

When it comes to getting rid of algae off the aquarium plants, the type of cleaning will depend on the type of plants in your fish tank. If it is only artificial plants, you can follow the same process as cleaning the rocks and tank decorations using boiling water and brushing the surface. You can also use the bleach solution if the algae are not removed but just make sure it is well-rinsed before returning to the fish tank.

If it is a natural plant, the cleaning will be complicated. But the process is actually similar to the artificial one but only handles it with care. You do not need to remove the plants if the algae are still few because you can simple brushed it off to remove them. If it is a very thick algae, you can remove the plants and scrubbed the algae using your bare hands. But make sure to do it slowly not to damage the plants.


How to keep algae out of the fish tank? There are many ways to do it, but the most important thing is to keep a routine when it comes to the maintenance of your tank to keep the algae at bay. Whether it is the preventive or the actual cleaning process, it must be done consistently to prevent algae from overgrowing in your fish tank.

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