RMR-86 or Marine 31 for "black dot" mold/mildew

granitehead · 06-17-2026, 06:42 AM

Has anyone done a head-to-head comparison of these two products for tackling this problem on both vinyl and gel coat? Or something else you've found effective?

Thanks!

burgerunh · 06-17-2026, 11:06 AM

I have had good luck on my old pontoon boat with RMR-86. I have never used the other product that you mentioned.

granitehead · 06-17-2026, 11:32 AM

Of course, there's RMR-86, RMR-86 Pro, RMR-86M Marine. If I choose RMR, I'm inclined to try the "Pro" as it's advertised as the strongest. I would think as long as I wipe down with water after, should be good...
I've tried most everything else on this persistent stuff.

fatlazyless · 06-17-2026, 05:31 PM

Suggest you try Miracle Mist, $9.47/qt spray bottle in the rv section at Walmart. ..... works fast to eliminate a super bad case of yucky black mold on vinyl or polypropylene(kayaks) and other materials.

Made by www.encorecoatings.com in Cartersville, Georgia.

06-17-2026, 06:42 AM	#1
granitehead Member Join Date: Aug 2012 Posts: 33 Thanks: 8 Thanked 9 Times in 4 Posts	RMR-86 or Marine 31 for "black dot" mold/mildew Has anyone done a head-to-head comparison of these two products for tackling this problem on both vinyl and gel coat? Or something else you've found effective? Thanks!

06-17-2026, 05:31 PM	#4
fatlazyless Senior Member Join Date: Apr 2004 Posts: 9,251 Blog Entries: 1 Thanks: 314 Thanked 1,120 Times in 827 Posts	Suggest you try Miracle Mist, $9.47/qt spray bottle in the rv section at Walmart. ..... works fast to eliminate a super bad case of yucky black mold on vinyl or polypropylene(kayaks) and other materials. Made by www.encorecoatings.com in Cartersville, Georgia. __________________ .... Banned for life from local thrift store!

06-17-2026, 11:06 AM	#2
burgerunh Senior Member Join Date: May 2016 Posts: 110 Thanks: 7 Thanked 42 Times in 26 Posts	I have had good luck on my old pontoon boat with RMR-86. I have never used the other product that you mentioned.

The Following User Says Thank You to burgerunh For This Useful Post:
granitehead (06-17-2026)

06-17-2026, 11:32 AM	#3
granitehead Member Join Date: Aug 2012 Posts: 33 Thanks: 8 Thanked 9 Times in 4 Posts	Of course, there's RMR-86, RMR-86 Pro, RMR-86M Marine. If I choose RMR, I'm inclined to try the "Pro" as it's advertised as the strongest. I would think as long as I wipe down with water after, should be good... I've tried most everything else on this persistent stuff.