Salt as a Treatment for Fish

Salt is a common and relatively inexpensive treatment for fish. The use of non-iodized table salt or rock salt (suitable for consumption by humans or livestock) is acceptable for treatment. For ease of application, many pond owners use 50 lb salt brine blocks. "Brine" blocks are salt blocks. Granular salt can also be purchased in bags or bulk.

Seawater contains 3% (30,000 ppm) salt concentration. Two hundred ppm (200 ppm) to 500 ppm can be used as an indefinite treatment in ponds to relieve stress. Ten thousand ppm (10,000 ppm) to 30,000 ppm can be used as a prolonged treatment in tanks for 30 minutes or until fish show signs of stress. Thirty thousand ppm (30,000 ppm) can also be used as a quick dip (60 seconds) in treatment tanks. To achieve 30,000 ppm in a tank, you add 2 1/2 lbs of salt for every 10 gallons of water. For ponds, 1 ppm is equal to 2.7 lbs/acre-ft of water. You need to know how many acre-feet of water you have in your pond (surface acres x average depth) to determine the treatment rate.