Ok, I'll try to get hands on him tomorrow, kids just went to bed. The flashing isn't a daily thing, maybe twice or three times in a week, usually one to three passes slightly more frequently on the side with the spot. I'm on county water, good quality with 0ppm ammonia. I use seachem prime. I've never used salt before, is there a special kind? How much do I use?Do I treat the 55 he's in or put him in a quarantine? Sorry for all the questions, I've not used salt or any meds before...guess it's been a lucky two years for a beginner.