recommended by Capt. Chuck on the Trawler "Beachhouse" and used by some with all good results..on many surfaces of varying prep and cleanliness. Not a miracle paint but the price and performance has been hard to match....and in every hardware store out there I think...
If you want to get fancy...a good 2 part epoxy is the best bet...but a lot of work and money...plus a misery to remove it if starts to fail.
Zinnzer Mildew Proof House Paint. Accept no substitutes....
Tintable, selfpriming, water based, non-toxic, 3 glosses, will not mildew, UV resistant.
Best stuff since sliced bread.