How To Remove Algae From Aquarium Decorations

How To Remove Algae From Aquarium Decorations
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If you’re new to the aquarium scene, you must learn how to maintain a healthy environment in your tank. Maintaining a suitable environment means controlling algae levels and keeping your tank clean.

One method to remove algae from aquarium decorations is by adding algae-eating fish such as the Siamese algae eater, which eats several types of algae, including black beard algae. Other methods include using a hydrogen peroxide solution and a white vinegar mixture. 

While we know a few methods of cleaning algae, there are still plenty of factors you need to consider, including which would be the most effective method depending on your needs. To help you figure out which method to use to clean algae from your decorations, let’s look at them in detail.

Methods of Removing Algae From Aquarium Decorations

In this section, let’s look into five methods you can use to control algae levels in your tank and thus keep your aquarium decorations algae-free.

Add Algae-Eating Fish and Snails to Your Tank

One of the most natural methods of removing and keeping algae off your tank is purchasing algae-eating fish. Several types of algae can grow in your aquarium, including the common brown algae (or diatoms), which is about 50% organic slime and 50% a mixture of bacteria, other algae, and small critters.

It is essential to select the right types and species of fish that can help with your algae problem since not all types of fish eat algae. In the case of brown algae, the bristle nose pleco would make a great addition to your tank. Amano shrimp and nerite snails are also excellent for controlling the levels of brown algae and thus removing that algae from your decorations.

Another common algae is the black beard algae, characterized by the black hair-like strands that it forms in your aquarium. The Florida flag fish and Chinese algae eaters are some types of fish that are brilliant at maintaining low levels of black beard algae.

Chlorine Bleach

One of the quickest methods of removing algae from your aquarium decorations is to bleach the decorations using chlorine bleach. However, you must ensure that the decorations can handle the harsh chemicals in the chlorine bleach, lest you ruin them.

To use chlorine bleach, you need to create a mixture of one part bleach and fifteen parts water in a large container that can fit all of your decorations. Next, add the decorations to the mixture and wait for the liquid to get to work.

You can leave the decorations directly in the bleach water for around 15 minutes at most, though if your decorations have more algae, it can require more time. However, do not soak the decorations for more than 45 minutes, as it can ruin and discolor them. Moreover, do not, under any circumstances, add chlorine bleach to your aquarium if it contains fish since it can cause significant harm.

Scrub the Algae Away

Scrubbing away the algae by hand is a straightforward and cheap solution to remove algae from your decorations. It can help clean your decorations thoroughly, and if you have a smaller tank, it shouldn’t be too difficult of a process.

However, if you have a larger tank with many decorations, it can become too much of a chore to continue scrubbing by hand. Furthermore, some decorations come in odd shapes that are difficult to clean by hand, meaning that you have to put a lot more effort into scrubbing.

Hydrogen Peroxide

Hydrogen peroxide is a natural solution to limit algae growth in larger tanks. To use hydrogen peroxide to remove and prevent the growth of algae in your aquarium decorations, you need to get the dosage exactly right to avoid any damage to your tank.

If you have a tank that is around 300 liters with a lot of blue-green algae, you can use around 48 milliliters of 3% hydrogen peroxide. For every 50 liters of water, you will need approximately 8 milliliters of 3% hydrogen peroxide solution. So, if you divide 300 by 50 and then multiply it by 8, you get 48 milliliters.

To add hydrogen peroxide, remove any fish from the tank and add the amount of hydrogen peroxide according to the calculation above into the water directly. Leave it alone for 15 minutes and repeat the process every day for the next three days. Next, you must change half of the water and add back all of the living creatures and plants.

White Vinegar Mixture

Using a mixture of vinegar and water is a convenient method to help successfully clean all the algae from your decorations. However, vinegar is quite strong and can thus irritate your senses if you do not handle it correctly. To use vinegar, ensure you are handling it in a well-ventilated environment and put on gloves and a mask.

Using white vinegar involves starting with a water container and adding around 120 milliliters of vinegar and around two liters of water. Add the decorations to the container and leave them alone for 20 minutes. After soaking the decorations, run them under warm water to remove all of the algae.

More Types of Algae and Algae-Eating Creatures

Due to there being numerous types of algae and even more species of algae-eating fish, let’s look more closely at how you can remove different algae from your decorations with the help of different types of fish.

One of the most common types of algae-eating fish is the Siamese algae eater, which you can identify due to its high energy levels and the long, black stripe down its back. Siamese algae eaters eat several different types of algae, including black beard algae, red algae, and green hair algae, thus helping to remove algae from your decorations.

Ramshorn snails are some of the most efficient algae eaters in freshwater environments. They often eat soft green algae that can grow on the surface of fish tank decorations. Ramshorn snails can also eat the brown algae that are more common in new types of tanks. Furthermore, since sea snails do not take up too much space, you can easily add more to help control algae levels.

The otocinclus catfish is also a very strong algae eater in aquariums. There are around 22 species of otocinclus catfish, and they can come in various colors to help diversify your tank. Otocinclus catfish have a peaceful temperament and can eat green spot algae, hair algae, and green dust algae, making them great additions to remove algae from your decorations.

Considerations When Using Algae-Eating Fish

Now that we’ve gone over the benefits of using algae-eating fish to help control algae levels, there are additional factors that you need to consider before using this method.


Take care not to add too many different algae-eaters to your tank, as it can lead to overcrowding. If your tank ends up hosting too many fish, then there is a chance that they may compete with each other and thus become hostile. Depending on the type of fish, they may end up nipping at each other’s fins and eventually tear them off.

Feeding Your Algae-Eating Fish

Although some fish eat algae, their diet cannot consist of only algae. Certain types of fish only eat algae to reach the bugs and critters in it. Furthermore, to keep your algae-eating fish healthy, you will need to feel them algae wafers or pellets.


Overall, you can naturally solve the problem of algae on your tank decorations by adding fish-eating algae and scrubbing by hand. Alternatively, you can use bleach, white vinegar, and even hydrogen peroxide. If you notice any bleach on your decorations, try using the above methods to handle the problem directly.

Image source: “Aquarium” by smerikal is licensed under CC BY-SA 2.0.

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