Old as Dirt!
Join Date: Nov 2008
Location: Tampa Bay Area
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Re: Black / gray deck spots - how to fix / prevent?
These weird and hard to clean spots have formed on my deck. They form in random patches. Please see these photos:
It's really hard to get them off - lots of scrubbing that I'm sure damages what's left of my non-existent gelcoat.
Does anyone have any idea what causes this? What I can do to prevent them? Also, any good ideas on how to clean it other than scrubbing and FSR?
It's called "Pinpoint Mold" and is growing in the pores in the GelCoat which is evidently very worn and has lost its glaze. Try covering it with paper towels soaked in chlorine from a pool company--not household bleach. The stuff will destroy the paper towel material quickly but should also destroy the mold if left over night.. Dose with a bit of Wink rust stain remover and then wash the area thoroughly with warm soapy water and rinse with fresh and then compound and polish. You've got to kill the mold spores and fill the Gelcoat pores. BTDT...
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