Here are the directions I follow--
FURAN-2
*Caution* using FURAN-2 as a zoa dip is different than using it for treating fish, the water to med ratio for a zoa dip is much different than what is given on the box.
Preparation: Prepare a container of water by dissolving one packet of FURAN-2 in one cup of freshly made saltwater (mix well). Raise the temperature of the water till it matches that of your tank. The water will be a greenish/yellow color.
Dipping: Place the polyps in the dip for as little as 5 minutes, but no more than 20. FURAN-2 works better at higher temperatures, so if you have the means slowly increase the temperature to 84° during the dipping process. If you can’t raise the temperature, be sure and maintain it at tank temperature. Remove the polyps and rinse in a container of tank water before placing back into your tank. Polyps may retain a yellow/greenish coloration, but that is normal and will go away in a day or two.
Polyps should be dipped once a day for three consecutive days. After completion of the dipping process allow a 5 to 7 day resting period before dipping again, if symptom persist. If you notice any adverse affects as a result of the treatment, stop treatment immediately.
Effectiveness: FURAN-2 is effective in combating both Gram positive and Gram negative bacterial infections, as well as fungus. It is also the primary recommended method of treatment for zoa pox.