Slimy Grimy
I had a dose of the dark stuff (as opposed to the white stuff) on my vinyl-type fabric on the walls of my vee & aft cabin.Wiping with an ordinary sponge and a solution of Slimy Grimy made it disappear. No apparent harm to the fabric.After a month of the boat closed and unused (damn rain), I do have some white stuff type of mildew on my wood, but the black has not returned.BTW, this stuff works great on the brown waterline stain. Spray it on and rinse it off - only light scrubbing is required.Rich