Brian I have been told this is from Tanins in the water. We had a white gelcoat (not painted) boat in an area where a larger river and swamp emptied into a bay. Especially at the bow this brownish/greenish stain was very noticeable. The product On and Off (oxylic acid I believe) tool the stain off very easily. Unfortunately it comes back very quickly. I was informed this was due to the porous nature of the gelcoat. The prevention for this was waxing the hull esp at the waterline with a high quality wax. Once we started being diligent with the waxing the problem went away.
... and when I say came back quickly I mean very quickly. We were visiting Charlottetown, PEI for a regatta and took advantage of their crane to haul to clean bottom. While out I scrubbed the hull above waterline with On and Off and removed the tannin staining. Charlottetown Harbour is where three good sized rivers meet. The stain was back in a bit over 24 hours. Mike Persistence Halifax, NS -----Original Message----- From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Brien Sadler via CnC-List Sent: Friday, December 14, 2018 1:59 PM To: cnc-list@cnc-list.com Cc: Brien Sadler Subject: Stus-List Hull products I’m looking for suggestions on a product to remove the the brown stain from my water line. Also, any recommendations on hull wax as well. Thanks, Brien Sadler TAZ 1987 C&C 35-3 Sent from my iPhone _______________________________________________ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray _______________________________________________ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray