6 Best Red Slime Algae Removers of 2019

Fish & Reef Safe Red Slime Eliminating Products

woman looking in algae-filled pool

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Red slime algae is actually not a "true" algae at all, but classified as a cyanobacteria. Often considered to be the evolutionary link between bacteria and algae, cyanobacteria are one of the oldest forms of life on earth and date back at least 3.5 billion years. These organisms produce oxygen as a byproduct of photosynthesis, and scientists believe that if it weren't for this microscopic organism, there would be no blue skies on Earth.

Commonly referred to as "red slime" algae, the name cyanobacteria literally means "blue-green" algae. Despite the naming, only about half of these organisms are actually blue-green in color. Most forms found in saltwater are other colors, ranging from blackish green to blue-green, from orange-yellow to reddish-brown, and often appear deep purple to fully black in color.

If you are you having a persistent problem with red slime algae (cyanobacteria) in your saltwater aquarium or reef tank, here are our top pick remedies that can be used to eliminate this nuisance algae when all else has failed to do so. As with any product one chooses to use, read and follow the instructions for usage as directed.

  • 01 of 06

    AquaVision Aquatics Cyano Solution

    AquaVision Aquatics Cyano Solution
    AquaVision Aquatics Cyano Solution. Photo by Price Grabber

    AquaVision Aquatics Cyano Solution is a antibacterial agent which treats unsightly cyano bacteria in marine and reef aquariums. Reef tank safe, it may be used in both marine and coral reef aquariums. Instructions read: Dissolve 1 scoop (included) with 1 cup of aquarium water for use with every 10 gallons. 2 grams treats 400 gallons.

  • 02 of 06

    Boyd Chemiclean Red Slime Remover

    Boyd Chemiclean Red Slime Remover. Photo from PriceGrabber

    Manufacturer: Boyd Enterprises | Features: Removes disease causing red cyanobacteria (red slime) from live coral; Removes red slime, black, blue-green and bubble producing algae; Oxidizes trapped organic sludge and sediment; Clarifies aquarium water to crystal clear; Promotes ideal enzyme balance; Contains no phosphates, algaecides or erythromycin succinate; Safe for fish, corals and other invertebrates, desirable macro algaes, and nitrifying bacteria; Fast acting, easy to measure and use powder; Does not discolor aquarium water; 2 gram size treats up to 300 gallons - 6 gram size treats up to 900 gallons. | Note: Recommended to provide additional aeration in the aquarium during treatment.

  • 03 of 06

    UltraLife Red Slime Remover

    UltraLife Red Slime Remover. Photo from PriceGrabber

    UltraLife Red Slime Remover removes red slime without harsh algaecides or antibiotics. UltraLife Red Slime Stain Remover is a revolutionary product that contains natural cellular matter, select biological accelerators and special supplements proven effective in removing red slime from corals and invertebrates.

    Manufacturer: UltraLife Reef Products | Features: Safe for fish, corals, invertebrates and other reef inhabitants; Fast acting, easy to measure and use powder; One bottle treats 250-300 gallons | Note: Causes skimmer overflow for days after treatment, so keep an eye on the skimmer collection cup levels to prevent overflow.

  • 04 of 06

    Blue Life Red Slime Control

    Blue Life Red Slime Control. Photo from PriceGrabber

    Manufacturer: Blue Vet RX | Features: Does not discolor the water; Will not harm any fish, corals or other reef invertebrates; Acts quickly; Easy to measure and use powder; Treats 400 gallons. | Note: If overdosed, this product could have some effect on pH and oxygen levels.

    Continue to 5 of 6 below.
  • 05 of 06

    Easy-Life® Excital Cyano Stain Remover

    Easy-Life® Excital Cyano Stain Remover
    Easy-Life® Excital Cyano Stain Remover. Amazon.com

     Remove stains caused by cyanobacteria without using algaecides or antibiotics! Excital Cyano Stain Remover offers a safe and easy way to restore aquarium beauty. Revolutionary blend of vitamins and synthetic concentrates stimulate the growth of beneficial micro-organisms in light-sensitive places in the aquarium. Healthy bacteria growth displaces cyanobacteria to clear stains from corals, live rock, substrate and other aquarium surfaces. You'll see visible results within 10 days!

    When dosing with your tank with Excital Cyano Stain Remover there is no need to turn off any of your aquarium equipment (protein skimmers, etc.) just remove any carbon in the system while using. No water changes are required afterwards because it's completely biodegradable. Safe to use with all marine fish, invertebrates and corals. Will not harm the beneficial nitrifying bacteria in your biofiltration system.

  • 06 of 06

    Ruby Reef Sliminator

    Ruby Reef Sliminator
    Ruby Reef Sliminator. Amazon.com

     Reef-safe and erythromycin-free solution to restoring aquarium aesthetics. Ruby Reef Sliminator water treatment eliminates unsightly slime caused by cyanobacteria. It contains no erythromycin and will not affect aquarium biofiltration. Safe for all aquarium fish (including scaleless fish), plants, corals. and invertebrates.