Fighting Algae

Algae are usually discussed in terms of warfare and destruction, but since they're both inevitable and necessary for fish to be healthy, aquarists must also learn the nuances of algae diplomacy.

What Are Algae? Algae are very simple plant-like organisms that grow in water. They are typically green and can appear in various forms, but without the stems, roots, and leaves of true plants. Algae are photosynthetic, so sunlight enables it to grow and feed off of available nutrients in the water. Fish owners dislike algae partially because it's not very attractive, but also because algae left unchecked can overwhelm an aquarium, reducing oxygen levels and creating a stressful environment for fish.

Prevention
The easiest way to deal with algae is through prevention. Avoid placing your aquarium in a place where it receives direct sunlight. Leave aquarium lights on for no more than 12 hours a day. Ensure that your aquarium has adequate filtration and water flow. Overfeeding also promotes algae growth through uneaten food left in the water.

Regular cleaning and water changes will also minimize algae growth, but be careful not to take an absolutist approach. Removing all algae from your aquarium can actually harm your fish.

Types of Algae
Algae comes in many forms and colors. It can be brown, green, red, or blue-green. Algae may manifest as spots, fuzz, beard or hair-like growths, or in strands like seaweed (which is also algae).

Remove algae manually from your aquarium about once a week. If algae is floating it can be hauled out with a net or twirled around a toothbrush. Algae dots that appear on aquarium glass will need to be scraped off.

Brown algae will usually appear in new aquariums sometime during the first three months. Take preventative measures, and the algae should disappear as the aquarium reaches a stable nutrient balance. Using reverse osmosis water instead of tap water will help control nutrient levels.

Algae-Eating Fish
You can also supplement your own efforts by enlisting the aid of algae-eating fish. Before you do, make sure such fish can live comfortably in your particular aquarium. There are several types of catfish that eat algae and don't grow overly large, such as Bristlenose and Whiptail. The Chinese Algae Eater and Siamese Algae Eater can also assist.