Susan Horton, DVM

What is Algae?

Algae should be thought of as a type of simple plant that develops when water and light are present. Algae is not harmful to an aquarium but in most cases is considered unsightly and customers want to control or eliminate it.

What causes Algae to grow?

For algae to grow it needs light. Both the aquarium and room light can cause algae to grow. If your tank is getting more than 10 hours of light a day you may notice green algae starting to grow. Warm water and ‘nitrates’ (which build up from not doing regular water changes) will cause algae to grow quickly. Also if phosphates are present, they will promote algae growth.

How to control Algae:

1)      Control the light received by the aquarium. The less light your tank gets, the less likely it is you will have algae.  Do not place your tank where direct sun light will affect the tank.  Keep your aquarium lights on a timer and limit the light to 10 hours a day.

2)      Regular water changes.   We recommend a 1/3 water change every 2 weeks for an established fish tank.  Algae uses excess fish food and fish waste for fertilizer. By doing regular water changes you will reduce the amount of “food” the algae has.

3)      Live plants fight Algae.  They compete for the same nutrients.

4)      Certain fish are “Algae Eaters” and will naturally help control algae growth.

5)      Many chemicals are available to help algae from growing. These chemicals are “inhibitors” and will prevent some algae from starting to grow but will not get rid of Algae after it has started.  We prefer a more natural tank without these chemicals and therefore do not recommend them.

6)      You may want to purchase a scraper or pad to remove algae from the sides of the aquarium. Don’t use anything from the supermarket to clean your tank, as it may contain soap which is deadly to fish!