Hmmm. Well, Hoppy seems to be a C. Orientalis (Chinese Fire-Bellied Newt) and if the spots were gone, I'd suspect they weren't actually areas of abrasion but of something stuck on him. I'd still isolate him and chill the water in case this is a fungus and watch him closely. There is also a section here on salt baths you may want to read in case it seems indicated down the road.
Problem is that these aquarium shops are getting these animals from the wild, hence the term we use here of WC (wild caught) as opposed to Captive Bred, CB. They are often gathered by the masses and transported in poor conditions. Those who do survive the trip are in poor health, subject to any number of diseases, then often kept in less than optimal conditions in the pet store. My pet store, where I bought my pair before being educated on this, couldn't keep their newts alive. My pair and one other woman's pair are the sole survivors and they don't even attempt to get them in anymore. It's too warm in there at night, not enough water, etc. Anyway, any of these pet store newts could be sick, though won't show it for weeks or longer.
Feed these newts a good, varied diet and keep us posted. I give blackworms and white worms (both from this site under For Sale/Trade) and frozen and thawed bloodworms. Earthworms are great for them as well.
Good luck,
Dana
