posted 09-02-2003 09:10 PM ET (US)
On and Off is a an acid compound. It works very well in getting rust and similiar stains out of the gelcoat. you basically wipe it on and wait 2-3 minutes, then hose it off. Reapply if necessary. We boat in heavily iron stained waters so we use it all the time. All of out boats have a deep oraange stain at the waterline if they are in the water 2-3 months at a crack.You can also use a commercial toilet bowl cleaner called Santeen. About 1.79 per gallon. Marine products are, like, $6 per quart.
Leaves in the boat will stain anything. They are full of, I believe, tannic acid and it is amazing how much they will stain.
To get out the stains you need to bleach them out, either with the sun or a product like On and Off. Happens to all fiberglass, care is the key (avoidance). Wax helps, but those darn leaves will get you every time. On and Off works great for them.
If you take your cover and wash it, it will get some of the excess color out.