I must share with you my latest discovery which has revolutionised my ability to clean even rust marks of GRP (fibreglass) boats.
It is simply to use "Cillit Bang".
That stuff is single-handed the dogs B*l*o*k* when it comes to boat cleaning.
I had to Google it to find out what it was made of and it appears to be containing industrial strength cleaning products, so that explains it.
Although I really do struggle to get that black, sooty, carbon blackness out of absolutely anything that has spent more than a couple of days in the Norfolk Broads...especially fenders.
Oxalic acid is what I use, it comes in powder form and you mix it with warm water and put it in a garden sprayer (oxalic acid comes from rhubarb) this is the same stuff as star bright hull cleaner. Oxalic acid can be bought of eBay for about £7 a tub and it will last you for years
A boat makes a big hole in the water in to which you throw money
CIF ain't too bad either although I suspect when it was JIF years ago it was a lot thicker.
It claims to be 100% natural products so I would imagine environmentally it should be okay to use on the Norfolk Broads waterways, I use the word imagine as I hold no data on this claim other than the label on the front of the product.
