Faded/dark areas on hulls

Going through the process of cleaning and polishing my boat and wanted to see if anyone could help me out. I bought some bar keepers friend and was scrubbing all afternoon. Only thing that I couldn't seem to deal with were the spots that I mentioned. I'm planning on wet sanding and polishing the hulls if that helps. Do I just need to keep at it?

https://imgur.com/a/N6jDjid

Hard to tell from pics just what those stains are. could be chemical or maybe even a mold. If your gelcoat is dried out and "Chalky", it is very absorbent to almost anything. You can try sanding, but maybe some chemical cleaners might be better. With the sanding, you may just find that stains like these can go pretty deep. West Marine has nothing for you to use?

It looks like mould. Try spraying with Exit Mould, Bleach or a similar mould removal product like you might use in the shower at home. Squirt area. Wait 10 minutes then wash off. It’s probably mould in the pores of the gel coat.

I use Exit Mould also on the inside of the hulls. Spray liberally in the hatch by reaching as far forward and aft as possible. Leave it for about 30 minutes or more then flush hull with fresh water.

Your boat will look and smell much nicer.

_________________
John Forbes
Hobie 18 Reimagined
Sail # 490
Boat name: 18@heart
http://www.hobie18.fun
https://www.facebook.com/Hobie18catamaran/