My boat had some stains in the gelcoat from the tannins in the CT river, I did a little reading and came across a product that was inexpensive, non-toxic and seemed to work well. All I used were gloves because it's an acid and some garage/shop heavy duty paper towels. Did a once over on the stains and waited about 15min, then was able to use the paper towel and remove the stains.
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