There is some anecdotal evidence that adding iodine to the tank may be helpful for both FW
shrimp while molting and snails in promoting harder shells. This evidence is inconclusive, but there is also no evidence that adding iodine is harmful when added in small quantities. The quantity needed in a FW
tank is less than in a Marine tank. I would think that most of the Marine Iodines could be used. On AppleSnail.net there are several posts mentioning that they are using Kent Iodine. I am using Seachem Iodide, which is another form of Iodine.