Algae buildup in a tank ruins the effect a nicely landscaped and designed tank can have. Algae clouds the glass and gives the water a murky glow. Algae blooms take oxygen out of the water, creating a health hazard to your fish. Algae competes with your plants for necessary light, and threatens their growth by taking nutrients away from them.

Algae ranges in both coloration and type. It can be colored green, blue-green or brown. It can grow in slimy sheets, brown clumpy patches; as a film on the aquarium glass; in thin, hard, circular spots; like a beard; or like hair (coarser than beard algae). If left undeterred, algae will actually bloom in large enough quantities to turn your water green.

A nitrate level above 10ppm is enough to get algae started on your fish tank. Ready and waiting for nutrients to become available, the algae spores multiply quickly.

Several solutions are available. The first, algaecide, a formula based on antibiotics or chemicals does kill the algae. However, in the long run, it leaves behind the nutrients that enable new algae to form and grow. Algaecides have long term impacts on your fish tank as well, if used too often or in the wrong way.

Lighting has an effect on both plant growth and algae growth in your fish tank. Placing your tank near windows that allow lots of direct light encourages algae growth, besides allowing for the possibility of your aquarium water temperature heating up too much.

Growing plants needs oxygen, so use air-stones to encourage your aquatic plants to grow. Algae, on the other hand, will see a decrease in growth as the live plants take back the nutrients in the water.

Excess feeding of your fish can also encourage algae growth if the food isn't eaten and remains in the tank. You can physically remove some kinds of algae from your water on occasion. However, don't use phosphate fertilizers, as algae thrive on phosphates. If you're going to use a fertilizer, use iron-based fertilizers to facilitate growth in your live plants.