That helped a lot! Unfortunately I have Cory catfish so I don’t think they’d like the saltWhat type of fish do you have? Did you remove chemical filtration (usually carbon)?
Raising the temp over 82°F is one natural and effective way to fight ich/ick if this is within a safe temperature range for your specific fish. Using aquarium salt is something I've found to help with gill flukes (and just about everything external, actually)... But I recommend microwaving some of your tank or treated water and stirring it into that to dissolve it first before adding it to the tank. Also keep in mind that aquarium salt is not recommended for plecos and for "scaleless" fish like loaches. Above all, water changes, water changes, water changes! And ammonia/nitrite should be zero.
Also, here's something I found that might be helpful from another thread... (Can Paraguard & PraziPro be used together? | Freshwater Fish Disease and Fish Health Forum | 85010)
"No they should not be used together. And I would do the one at a time suggestion. And if neither work then try changing to a different medication after a 50% water change at least. Medications take a lot of time to really get out of the tank even with carbon...it just stays there in that case. Its best to take it one at a time. I would also research and see what all can cause scratching. Maybe something else will come up"
Hopefully the link worked...
Best of luck with your fishies!