I have found that a lot of the Ick medications often contain copper..even on time when it is not listed on the bottle it is still there in small amounts. Typically when you're piling these medications into the tank snails are not taken into consideration - copper is harmful to snails. Which is likely why you lost the little guy if you were using some of these medications.
In my experience the best (most natural way to tre at Ick) is with aquairum salt (the kind meant for freshwater tanks) and increasing the tempreature. Salt should be added gradually with water changes and temperature should also be increased gradually as to not shock the fish....which I'm sure you already know.
I see that this post is older and you have resolved your issue but should you run into this again I would advise trying salt and increased temps for awhile before the medications. Salt and increased temp often takes a lot longer to cure the situation depending on how bad of a case you have on your hands - but in the end everyone usually pulls through.
Also, you can add some salt to a healthy aquarium to keep your fish in better health and to better prevent ick.
Here's to hoping you stay Ick free in the future.
