One day I am going to have the time to compound and wax after cleaning the hull, so will then get to see if the stain stays away for any appreciable time. I know a fellow who had a terrible time with the stain on his bows, until he got an Awlgrip paint job. No stain since, suggesting that the stain likes older gelcoat, where it can get a grip.
I am not the guy with the right answer.... so hopefully some will help.
Wax seems to be an issue with soot from exhausts and the brown mustache.
I have heard that polish works better but can't recommend anything.
Hold the wax till you hear the tales.....
If "On and Off" or toilet bowl cleaners or other acid product remove the stain, it's not tannins but something else. "Tannic acids" are neutralized and removed by basic products. Stains in stainless coffee carafes and teapots are typically removed by TSP or caustic soda. I suspect the brown stains on boats are iron oxides and are therefore most easily removed by oxalic or nitric acid.
Jim
Sent from my iPad using Trawler Forum
If "On and Off" or toilet bowl cleaners or other acid product remove the stain, it's not tannins but something else. "Tannic acids" are neutralized and removed by basic products. Stains in stainless coffee carafes and teapots are typically removed by TSP or caustic soda. I suspect the brown stains on boats are iron oxides and are therefore most easily removed by oxalic or nitric acid.
Jim
Sent from my iPad using Trawler Forum
Are mustaches only common on white/light-colored hulls? Never had an issue with my dark-hulled boat. But neither did my Dad in the polluted 1960s SF Bay with his egg-shell colored sailboat used in salted water. Is it a fresh-water issue?