Hull and waterline stains
Marykate On & Off Hull & Bottom Cleaner
Tested by us.
An acid-based cleaner for waterline and hull stains. A go-to for regular stain removal.
See price on AmazonStar brite Instant Hull Cleaner
Tested by us.
An oxalic acid cleaner for scum lines and waterline stains.
See price on AmazonAcid cleaners leave the gelcoat bare. If the area has oxidation or scratches, fix those first, then wax or seal it. Wear gloves and eye protection, keep it off metal like a galvanized trailer, and never mix cleaners.
Mildew
Star brite Mildew Stain Remover
Tested by us.
A spray-on mildew stain remover for boat vinyl and hard surfaces.
See price on AmazonConcrobium Mold Control
Removed mildew from a test carpet and kept it from returning in Practical Sailor's testing.
Basis: Practical Sailor mildew treatments test, about 2022 (exact date to confirm).
See price on AmazonKeep bleach-based products off canvas and stitching, since bleach can weaken fibers.
How to use them
See our hull stain guide and mildew guide.
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Timmy Mohar, Nautical Glow Marine
I run a boat detailing business in Southwest Florida and on the North Coast of Ohio. I have spent every year of my life around boats and taking care of them. About this site