Basically what the title says. Have a raised white mark on top of nuchal hump. Pics. Had a mini cycle. Ammonia was at .25 did water changes prime etc. now it's all normal 0-0-~25/30 is there anything I should do or just wait and watch? Thanks.
Could be an abrasion or slime coat peeling from the ammonia. Keep the water clean and add some salt(1 tablespoon per 5 gallons). Should be better in a week