My boat sits on a lift at a marina and once this summer the lift sprang a leak and the boat sat in the water for a week. What's the best cleaner to get the stain off the fiberglass.

The Works toilet bowl cleaner. Squirt it on then brush lightly and rinse. You'll need to was afterwards.

I'd try Slick Mist, or Bass Boat Saver, or Bling, or maybe just water and a rag first.

The Works will take it off, but will also take off any wax you may have had on the boat.

The milder, the better. Most bathroom cleaners will work on surface stain, but remember almost all will have some acid of sorts. Protect that trailer, rinse off thoroughly and wax hull / lubricate hardware.

I used Soft Scrub on some stains on mine. Texoma will leave some nasty stains just in the water overnight. Also tarnish a polished prop.

I’ve used Starbrite Boat Guard and have really pleased