How to Stop Brown Algae in Aquariums

Although unattractive, the existence of algae in an aquarium does not indicate a dirty tank. In fact, algae is the primitive form of a plant-like organism. It is not uncommon for brown algae to appear in a newly set-up aquarium then disappear after tank becomes ecologically balanced. The lack of any algae growth in a tank indicates an unhealthy environment, which may also be unhealthy to the fish as well. Although an aquarium cannot be entirely algae-free, actions can be taken minimize its presence.

Things You'll Need

  • Algae eating animals
  • Aquarium thermometer
  • Aquarium scraper tool
  • Aquarium vacuum
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Instructions

    • 1

      Reduce the amount of light the aquarium receives. Move the aquarium away from the window or draw curtains or blinds to limit direct sunlight. The use of artificial lights should ideally be limited to eight hours per day. More than 10 hours light per day will quicken algae growth.

    • 2

      Add algae eating animals to the tank. Blue-legged hermit crabs, sally lightfoot crabs, snails, urchins and some catfish will help clean the glass, ornaments and gravel.

    • 3

      Monitor the amount of food given to the fish. Overfeeding fish will increase the nitrates algae need to grow. Reduce feeding if food is collecting at the bottom of the tank uneaten.

    • 4

      Adjust the aquarium heater to maintain a water temperature of 78 degrees Fahrenheit for fish-only tanks or 74 degrees to 76 degrees Fahrenheit for tanks where reef and plants are also present.

    • 5

      Clean the tank glass and gravel on a monthly basis allowing some algae to remain. Lack of algae altogether will encourage new growth faster. The glass should be cleaned with a scraper tool; the gravel with an aquarium vacuum.