Hey folks - I came home from vacation to a sick tank. No new additions in better than a month. My tang died before I could get him into qt. Now my fox face has these spots and I’m not sure how to treat. I’m wondering if they are nem stings? While I was gone, 1 wk, the ato failed and our house sitter didn’t catch it. It took 6 gallons of RO to fill a nearly dry (gurgling) sump. My tank and sump are ~95 gallons. Thanks for your help.