I always use the raise the temp in my tanks for two weeks if I notice any ich, and I have never lost a fish to it Be careful of using salt. Some fish such as plecos don't tollerate it well at all.
How high have you raised your temp too? I’m trying this method out because I fed my Jardini a swordtail fish I had for months but he couldn’t catch it and developed stress ich lol. Tank is planted heavily so trying to raise it to 89.5F for 3-4 days then 86F for 6-7 days after.