iodine question

They must be something else wrong because snail`s hermits are near enough bullet proof is your salt level / temp ok?? you don`t really need iodine as your salt mix will have plenty in for now you only use iodine if you have lots of corals & your iodine level drops which is rare if you do weekly water changes..

maybe someone else can give you the answer why your snails & hermits died but i`m a little clueless if all your tank heat/salt/water is perfect

unless is there any copper within the tank or metel???

It may not be metals.. Please post a full list of your parameters.. Ammonia, Nitrite, Nitrate, PH, Alk, Temp etc etc etc. How long as the tank been up. A more complete picture is needed before any true diagnosis can be made. What are your calcium levels? What are you dosing? YOu said you have been buying junk chemicals for your tank.. What exactly are you putting in your tank vs what you are testing for..

Ditto to what Clown said. We need info.

I agree with the above. Iodine is most certainly not your problem. This is one of those manufacturer-perpetuated hobby myths (they tell you they need iodine, but not how). Shrimps and crustaceans do not need iodine in the water column. In fact, they do everything in their power to get RID of it (they concentrate iodine into a molt to get rid of it). That is not to say they don't need iodine at all, which certainly isn't true--they need it in dietary form from high quality seafoods, etc. In general, I don't recommend adding iodine directly to the water in the first place for a number of reasons.