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How to Keep Fish Aquariums Algae Free

In the following article you will find some basic information on How to Keep Fish Aquariums Algae Free. Every aquarist must battle green algae growth on the walls of the fish tank. The following article will tell you how to prevent algae from over running your aquarium.

How to Keep Fish Aquariums Algae Free

One of the most common problems people have when they set up a home aquarium is green algae growth on the walls of the tank. Taking the following points on prevention and eradication of algae into consideration will help keep your aquarium clean and algae free.

Location and Lighting

When setting up an aquarium, keep it away from windows. Intense light from the sun provides algae with the energy it needs to grow, spreading an ugly green mess throughout your fish tank.

Do not leave the lights of your aquarium on too long. Twelve hours a day should be the maximum, and if you still have algae problems, cut it down to eight. Plugging the lights into a timer may be helpful if you are not always home to turn out the aquarium lights.


Algae often proliferates in an aquarium where the fish are overfed. Leftover food that the fish don’t eat and sinks to the bottom creates an overabundance of nutrients that feeds the algae. Only feed the fish as much as they can eat in two to five minutes, and never let any food sit at the bottom of the tank.


Regular aquarium maintenance will help prevent algae blooms. Every three weeks about twenty percent of the water should be siphoned out of the fish tank. Make sure you siphon the gravel well, as this is where waste builds up, and provides a source of nutrients for algae.

Remember to always add water conditioner to any newly added aquarium water, as cloramine in tap water will also feed algae.

Live Plants

If your aquarium comes with florescent lights, adding a couple of aquarium plants is wise. Not only will they use up nutrients created by fish waste before any algae can, they also add to the aesthetics of the aquarium, giving it a more natural look.

Algae Eaters

There are fish you can add to your aquarium that will eat algae.

The Plecostemus, or “Pleco,” is a favorite amongst aquarists to help keep algae under control. It often outgrows its tank though, as depending on the species, it can get over two feet long. Stores that sell fish will often let you trade a big Pleco for a small one if it gets too big for your tank.

If you have a very small tank, the Ottocinclus or “Otto Cat” may be a better choice, as it only grows to five or six centimeters.

The Gynocinclus, which is often called the “Chinese Algae Eater,” is also commonly used to eradicate algae in a fish tank. These fish do a great job when they are young and small, but as they age, they stop eating algae, and often become aggressive.

Snails can also help eat the algae in your aquarium, but not all of them eat algae, so make sure you know what species you are adding to your aquarium.

Filter Media and Phosphate Removers

Carbon and ammonia removers are the main components of filter media in home aquarium set-ups. They are added to filters to help absorb harmful waste materials, which can feed algae. They only last for a month though, so changing them regularly will help keep algae under control.

One of these harmful waste products that can be present in aquarium water is phosphate. If all else fails, adding a phosphate remover to the filter will help get rid of algae.

It can be tough to get rid of algae once it spreads throughout your aquarium, but diligence and regular maintenance will keep your fish tank crystal clear.

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