How to Salt an Aquarium

Aquarium salt is a product that may be added to a fish tank to bring it to a therapeutic or treatment level of saltiness for freshwater fish. This product differs from table salt in that it lacks iodine and calcium silicate, additives that humans need but fish don't. Be sure you know your variety of fish and understand its tolerance for salt prior to treating the water.

Things You'll Need

  • Aquarium salt
  • Aquarium for setting up hospital tank
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Instructions

    • 1

      Add 1 1/2 cups of aquarium salt per 10 gallons of water in your tank to treat your fish for ectoparasites. These are parasites that live on the skin of your fish. When measured on a standard marine aquarium hydrometer, the parts per thousand should read between 7 and 13. Maintain this level of salt for three weeks then switch back to fresh water. Freshwater fish that can handle this much salt are Central American cichlids and livebearers, African rift lake cichlids and Koi.

    • 2

      Prepare a hospital tank for fish that have ectoparasites but can't tolerate a long time in salt water. Add 1 1/2 cups of aquarium salt per 10 gallons of water. Add your fish for between 30 minutes and two hours as a dip to kill ectoparasites. Pay close attention to your fish and remove them to fresh water when you see any sign of distress. Fish such as the corydoras catfish and many live aquatic plants won't tolerate this level of salt for even short periods of time.

    • 3

      Add a therapeutic amount of aquarium salt, 1 teaspoon per 10 gallons of water, to your a freshwater hospital tank that holds fish that have lost a significant amount of scales or damaged skin. The salt helps your fish heal and keep their blood salt levels where they need to be. Keep your freshwater fish and plants in this concentration, which is enough to kill many pathogens but won't adversely affect most varieties. At the first sign of distress or illness in your fish, prepare a hospital tank with a higher quantities of salt.