Iodophors are iodine containing, non-selective liquid germicides which are active against many bacteria, fungi and viruses. iodophors have not been registered by the Food and Drug Administration as a disinfectant for use with tilapia or other fish cultured in the United States. Iodophors are widely used as a disinfectant in human and veterinary hospitals and terrestrial animal industries. Although not formally approved for use in food fish culture, commercially available iodophors are widely used for disinfection of green or eyed eggs, containers, equipment and had and foot baths in fish culture worldwide. Some of the common commercial products include Wescodyne (trade mark), Betadine(trade mark) and Argentyne(trade mark).
For tilapia culture iodophors have been used to disinfect equipment, containers, to clean hands or in foot baths. Suggested iodophor dosage for these applications range from 50 to 250 mg/L (ppm) as free iodine. Solutions should be made fresh. Previously cleaned equipment or tank surface can be sprayed with the dilute iodophor solution and left to dry for ten to fifteen minutes before the iodine is rinsed off with clean freshwater. Alternatively, an iodophor bath can be made in freshwater and equipment, hands, the bottoms of foot gear dipped into the solution. Equipment should remain in contact with the iodophor for ten minutes before removal, rinsing and be hung up to dry. Commercial iodophor products come as liquids with 0.5% or 1.0% available iodine. Working strength solutions should be prepared in freshwater (saltwater should be avoided).
Iodophor solutions used in foot or equipment disinfection baths can be used over several consecutive days, but should be discarded once the solution becomes slightly transparent (two to three days in most applications). Iodophors are not very effective in the presence of organic matter. Thus, equipment, etc. should be scrubbed to remove dirt or other material before being disinfected with iodine.
As iodophors are not FDA registered and approved for use in tilapia culture, these disinfectants should only be used on tilapia farms under the direction of an active INADA for such use.