I've had some trouble getting the black stains from the port hole run-off removed. I tried all kinds of stuff. After reading a comparison test in Practical Sailor, I decided to try the Nautical Ease Anti-Skid and Black Streak Cleaner (or something to that affect). It worked beautifully. Also took off scuffs on the hull from a less than graceful docking incident.
Directions say to spray on, wait 10 seconds then buff off. All I had to do was wet a section of cloth and wipe away. The marks came off nearly as easily as wiping grease off a stove. I was quite amazed after all the other product I tried.
I bought the stuff on the internet. I don't know if you can get it at any of the marine supply stores.
Rperlot
CD28 #352
Product Endorsement - black mark remover
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