How to Dissolve and Cure Ich

Ich, caused by the protozoan Ichthyophthirius multifillis, is a common disease found in both salt- and freshwater aquariums. Ich appears as white pimplelike dots on the fins, gills and body of the fish. By this time the ich is in its trophont stage; it has already burrowed under the fish's mucus coat and can become lethal to the fish if left untreated. Symptoms of ich are rubbing against objects in the aquarium, often referred to as "flashing," lethargy, tilted swimming and labored breathing. Fortunately, ich can be treated; however, some chemicals cannot be used for scaleless fish, such as the loach and catfish.

Things You'll Need

  • Underwater heater
  • Aquarium thermometer
  • Methylene blue
  • Formalin
  • Malachite green
  • Second aquarium
  • Sponge filter
  • Measuring spoons
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Instructions

    • 1

      Set up a quarantine tank that has been chemically treated with either formalin or malachite green. Follow the manufacturer's directions on the bottle for proper dosage. The quarantine tank will house the fish for the next few days.

    • 2

      Raise the temperature of the infected aquarium to between 80 and 84 degrees F. Trophonts and tomites cannot tolerate warm water and will not survive without a living host. By raising the temperature and removing the fish, the life cycle of the parasite breaks and the parasite dies. After four days return the aquarium to the proper temperature.

    • 3

      Run the filter in the infected aquarium continuously. Remove the charcoal from the aquarium filter and run only with the sponge inside. Keep the filter running to filter the water and capture dead parasites.

    • 4

      Assess the fish in the quarantine tank several times per day while the main aquarium is under treatment. Look for signs of stress or improvement and remove any dead fish. Between two and four days after adding the chemicals to the temporary aquarium, any trophonts and tomites will die, therefore breaking the ich cycle.

    • 5

      Look for signs of the parasite on the fish in the quarantine tank. There should be no visible signs of the parasite present on the fins or mucus layer before transferring the fish back to the original aquarium.

    • 6

      Give scaleless fish such as loaches and catfish a methylene blue bath. Follow the manufacturer's directions on the bottle for proper dosage and mixing instructions. Typically a methylene blue bath lasts 30 minutes and will stain the mucus coating of the fish blue.