Be careful adding the salt direct to the tank. I used 2 teaspoons per gallon predissolved in a 5 gallon bucket and added gradually over the course of a day. I was treating pictus cat, balas and some CA cichlids and had good results.
Scary when I only had them 2 weeks cost about £300- £400 for my fish. Got the Mrs to tip the salt it. I didn't wana finish them off. I can blame her if anything goes wrong lol
Now she has to buy more fish if anything happens lol. They should all be fine tho, I've had groups of clown loaches get ich, treat with salt and heat and no losses. If you can, do daily or every other day wc to get the free floating parasites out to keep them from reproducing. Can't do anything when they're attached to the fish. Heat speeds the life cycle, salt and wc stops reproduction