How to Get Rid of Red Algae in Salt Water Tanks

Red algae is a pervasive problem in salt water fish tanks less than six months old. If it is improperly dealt with early in the life of the aquarium, it can recur in a pernicious cycle that is difficult to break. By using patience and natural methods to control and eliminate your red slime algae problem, you will be able to fully enjoy your salt water aquarium for years to come.

Things You'll Need

  • Distilled water for your tank
  • Gravel vacuum
  • Replacement filter pad
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Instructions

    • 1

      Clean your aquarium filters regularly. This means about once a month in most cases. If you clean your filters more often than this, your fish may die from the shock to their systems. However, clogged filters contribute to the high phosphate levels that feed red slime algae. Filtering these nutrients out will not hurt your fish, and it will starve your red algae. Generally, you should rinse out your filter sponge using a small amount of distilled water, then replace the old sponge back in the filter. If the sponge is too dirty to clean, replace it with a new one.

    • 2

      Clean the protein skimmer biweekly. You can clean your protein filters using either distilled water or the water from the aquarium to limit the impact on your fish. The important thing is to keep that skimmer clear and running smoothly, so that the algae won't have enough to eat in your aquarium.

    • 3

      Use distilled water in your aquarium. If you use tap water in your salt water aquarium, you likely are feeding the red slime algae and adding to the problem. Most tap water has added phosphates that the algae will thrive on. Using distilled water will eliminate this issue and quickly starve out your slimy invader.

    • 4

      Vacuum the gravel about once a month. Debris from uneaten food, waste and other aquarium byproducts adds to the potential food sources for red slime algae. Cleaning out the bottom of your tank where this debris collects will minimize the potential for algae growth.

    • 5

      Give your fish room to swim. Overstocked aquariums accumulate nutrients in high concentrations in the salt water. This leads to algae growth. If you have an additional tank, try reducing the number of fish in each tank. Because the nutrient concentrations are specific to each fish's "output," it is hard to say exactly how many fish are right for any one tank. You may need to experiment with different fish combinations and populations until you get one that is right for your aquarium.