Just the typical off the shelf iodine that you would use on the kids. Use a Q-tip and swab the infected area. Don't be too gentle as you want any necrotic tissue cleaned away, leaving nice fresh edges. This should only be done once.....if the water is good and there's an antibiotic in the water then within a few days you should see some new growth or a white film develop.
Use caution and don't get iodine in thier mouth, eyes or gills
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