Re: OK, so I'm Sanding My Bottom...
Since you're sanding that super toxic stuff, I assume that you have all 147 permits that are required and that you've conducted fish impact studies as well using EPA certified salmon psychiatrists....
PS That grey matter looks like the real fiberglass of your hull. Me thinks you went a little too deep there. Perhaps a lighter grit sandpaper would be better?
"True, your boat will outperform mine to windward, but my boat will always outperform yours at anchor." --MedSailor