After over 50 years of cleaning boats I just found a new stuff that made my day. So good I had to pass the word (I have no commercial interest and in fact don't even know who makes it).
My Nonsuch 26 is usually spotless and I paste wax it once a year. The problem has always been those rain streaks which no boat soap seems to clean off. I always had to use 3M cleaner wax or some such to get those off and have the boat ready for the wax. Today I easily wiped the hull topsides with one of those pot scrubber cloth things, hosed it off and voila!, spotless and ready for wax. What used to be a couple of days job took all of 30 minutes. It even took off some of the rub marks and cleaned the shore power cord.
It is called Shell Buseys's Home Cleaning Formula and I got mine at Home Hardware after a friend referred to me to use it for the vinyl deck on the house. It is slightly corrosive so hosing off really well is important.
Where I left it for a bit on the aluminium hull rail little white spots appeared but these wiped away with a damp rag and would have flushed off with the hose if I had been attentive earlier.
I guess if you left a strong solution on the metal for a long time you would not be happy. Anyway maybe this is old news to many of you but it was a new wonder for me and maybe some of you will benefit.
*NOTE
Bob D'Arcy