I park my car in a carport. I have a canvas top. The driver's side is inundated with moisture. Rain and morning dew mostly. Because of this my 2 1/2 year old top had acquired a nice growth of mildew all along the rear deck and the whole driver's side. The picture doesn't do it justice. It looked terrible.

I was told this product called iosso would remove it, with out causing any long term damage like bleach or vinegar would. It's an enzyme that just eats the mildew.

I skeptically tried it. The instructions tell you to wet the top, apply a coat of product and don't let it dry. Keep it wet with product. I did that for about three hours, let it sit overnight, then gave it another three hours wet. Then just rinsed and washed. Every bit of mildew is gone. Now I have to get a can of Raggtop to make it bead again. It works on vinyl tops too.