I'd add an airstone or bubble wands with an adequeate pump, raise the temp to at least 86 and keep it there for two weeks. They will look better after maybe 5-6 days but do not turn the temp down then because ick can stay in your tank after it falls off of your fish for almost another 8-9 days in my experience. What size tank is it? 12 tablespoons might be too much or too little you want to put 1 tablespoon of aquarium salt per 10 gallons, some people even do per 5 gallons I have succesfully done it with just using one tablespoon per 10 gallon method. Good luck.