Green Water

Why is my aquarium water green?

The water is green because of free-floating planktonic algae in the water. Algae, being a plant, requires light and nutrients to grow. In an average community aquarium with live plants, we recommend 8-12 hours of artificial light. In tanks without any live plants, we recommend that the lights be on only for your viewing pleasure. Clock timers are a good way to control the duration of light. Sunlight can also cause an algae bloom. We don't recommend that you place the aquarium in direct sun. Please be cautious in placing the tank in a brightly lit room, i.e. greenhouses and sunrooms; as indirect light can also cause an algae bloom. With the change in seasons, the sun's position in the sky will change and may light the room too brightly. The other factor that can cause your water to turn green is the nutrients in the water. Nutrients in our aquariums include: fish wast, the products of decay, and prepared plant fertilizers. Having too many fish in the aquarium, having excess food in the tank, and overdosing prepared fertilizers are sure ways to get green water.

How do I get rid of the green water?

A sure-fire way to eradicate the green water is with the use of a good algae-cide. Usually it comes in a liquid or in a tablet form. Simply follow the directions on the package. Be sure to remove the carbon and any other chemical filtration media from the filters as they will remove the algae-cide from the water. We normally would not recommend the use of algae-cides with live plants. In this case, we would seek out the cause of the green water. In most situations, a combination of too much light and too much nutrients in the wter is the cause of green water. Reducing the duration and intensity of light is a way to clear the water. The use of clock timers to control the light duration is highly recommended. Drawing the blinds and curtains to block sunlight is also recommended. As for nutrients in the water, a good water change is recommended. Changing the water will remove some excess nutrients. Be sure to remove all excess food from the aquarium. This includes the food trapped in the filters. Be sure to clean the filters frequently, as decaying material in the filter will relesae nutrients in the tank. Adding more live plants to a tank will also help. Live plants are more competitive than algae are. They are larger, so they cna shade the tank some. They are better at utilizing low levels of nutrients from the water than the algae can. So, with lots of live plants, the algae will be starved out.