I had ick in my 20 gallon fresh water tank and I cured it in the following way:
Up your water temperature to 85/86 F leave it like that for 2 to 3 days and ick will DIE! No chemicals or nothing needed
I'm sorry, but fresh ick and salt ick are two different things. This will not work for his fish. In fact, it speeds up the cycle.
15, it looks like someone sprinkled salt on your fish. After a couple days, no salt and then it starts over again.