Tammo - I brought a product at the boat show last year - I think it is called Star Brite ( American product) to clean all the algea and crap of my hull as on the one photo, this stuff was amazing it removed all stains no problem. So I'm sure their polish will be excellent as well.....
There are water marks but tried to get it out with rubbingcompound does not work can some give me some advice on how to get it out and the stainless steel t-top have some rust what can I use the polish the stainless steel