In the creek yesterday I checked the prop on the sailboat and it was crusted with barnacles again. I had just scrapped it clean about 3 weeks ago. With a prop crusted with barnacles the prop will just spin and the boat will not move forward. This has been the talk of the marina this year every one has had a diver come in and clean their prop ( for $60!! ) or had their boat hauled out of the water to have it cleaned. ( for about $150!!!) The barnacles have attached themselves to the props and shafts. Not to the bottoms as far as I can tell. Lucky thing that I can reach the prop easily and do not have to dive to clean it. This has saved us at least $120 as we had to do this twice this year.