The Hobie cleaner also makes short work out of petroleum residues, which are especially noticeable on white hulls. Here's a before and after looking in the drivewell:
Hobie also sells a protectant. I spray it on, spreading it with a damp cloth. Once dry, it lasts awhile and puts a nice shine on the boat. Here's a shot of the bottom of my 3 year old Adventure this morning. It has logged over 1000 miles, mostly in dirty water.
Be careful though -- it makes the surface very slick, so be mindful where you use it!
For deeper cleaning and removal of more stubborn black streaks from the rack, I use an automotive cleaner-wax, mostly for the cleaner. Maguires works well for this purpose.
