Be careful when looking to dose iodine. It is easy to overdose. Most salts will have enough for the average aquarium including mantis tanks IMO. My 12 gallon eclipse has been fine for my 2.5 inch mantis for a few months without iodine supplementation. He has molted at least once. Additionaly, my 40 gallon supports 2 peppermint shrimp, 2 saron shrimp, and several hermit crabs and they molt just fine - all without iodine supplementation.