I do a 1 part bleach to 19 parts water and a 4 minute dip for large leaf plants and 2 minutes for mosses and small leaved plants. I hear some plants don't do wll with it but I haven't seen any problems on mine including Crypts,swords,java moss, and baby tears.
Potassium permanganate is another option...I haven't tried it.
I used a salt water treatment for
ICH and while the plants did not like it (2 died) the others made it ok. It did NOT however kill the snails. In fact I would say they are worse now than they were before. In the future I will do the bleach dip AND quarantine all plants for a minimum of 2 weeks. I am 99% sure that the Ich came in with some new plants I bought. (They had fish in the plant tank that had iCH)