How to Get Rid of Ick on Your Fishes

If there is one syllable that strikes fear into the heart of fish fanciers, it's "ich" (often spelled "ick"). This condition, also known as white spot disease (scientific name ichthyophthiriasis), can cause respiratory distress, agitation and even death. It is carried by protozoa, and is widespread in all freshwater fish, with aquarium-kept fish at special risk. Because ich protozoa are so prevalent, most fish have good resistance to them. However, when fish are stressed, they become vulnerable. Fish with ich exhibit growing numbers of white dots that resemble grains of salt, and they often rub and scrape against objects. If your fish have come down with ich, there are steps you can take to restore them to health.

Things You'll Need

  • Bottle of commercial ich medication
  • (containing either malachite green or methylene blue)
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Instructions

    • 1

      Slowly begin raising the temperature of the tank until it reaches between 78 and 80 degrees. Ich cannot be treated while it is on the fish, since medication can't penetrate the cysts, or trophonts, that hold the protozoa. The trophonts eventually leave the fish and divide into multiple tomites, or ich-infecting units, which have only 48 hours in which to infect fish. It is at the tomite stage that ich can be most successfully treated. Heating the water speeds up the life cycle and makes treatment more effective.

    • 2

      Shut off the carbon filtration system and remove the carbon.

    • 3

      Begin medicating the water with a commercial ich remedy containing either malachite green or methylene blue, chemicals that are effective against tomites. Follow dosage directions exactly. If you have scaleless fish such as catfish or tetras, you should cut dosage by half and monitor fish for signs of distress.

    • 4

      Continue the course of treatment for the recommended time, usually 10 to 14 days. Keep the temperature in the tank elevated and the filter shut off in order to prevent dissipation of the beneficial chemicals.

    • 5

      After the first week of treatment, do a partial water change.

    • 6

      When treatment is complete, gradually return tank to normal temperature. Change the carbon in the filter and turn the filtration system back on.

    • 7

      Prevent ich from developing in your fish tank by quarantining all newly-acquired fish for at least two weeks. The fish might have experienced overcrowding and improper water temperature during their journey from place of origin to your aquarium, putting them at risk for disease. New plants being introduced into your aquarium should be treated with ich medication.