How to Get Rid of Red Coralline Algae in a Saltwater Aquarium

Red coralline algae is a type of coralline algae that thrives in well-balanced saltwater aquariums once a live rock has been introduced. It is a sign of a healthy saltwater aquarium, and inhibits the growth of other less desirable algae, such as hair algae. Normally the growth of red coralline algae is encouraged, but some aquarists prefer to remove it when it covers the sides of an aquarium or any decorations in the aquarium.

Things You'll Need

  • Plastic or metal scraper, old credit card, or razor blade
Show More

Instructions

    • 1

      Siphon about 10 percent of the water out of your saltwater aquarium so it doesn't overflow when you reach your arm in. Use the same siphon hose and bucket you use for routine water changes.

    • 2

      Strip your arm to the shoulder and wash it with soap and water. Rinse thoroughly to avoid transferring any soap into the aquarium. If your aquarium is deep and your arm will be in up to your armpit, remove your deodorant.

    • 3

      Choose the tool you'll use to scrape the red coralline algae from the sides of the saltwater aquarium and wash it with soap and water. Rinse it thoroughly. For acrylic aquariums, you'll want to use a plastic scraper or an old plastic credit card. For glass aquariums, you can use a razor blade or metal scraper.

    • 4

      Reach your arm into the aquarium and hold the tool against the glass at a 45-degree angle. Scrape up or down gently to remove the red coralline algae.

    • 5

      Let the loose pieces of algae drift to the bottom of the aquarium. They'll likely reattach somewhere else and continue to grow. The filter might remove some of the algae pieces, but coralline algae helps maintain a well-balanced and healthy saltwater aquarium, so it does not need to be removed.