Well he ended up getting that little device called the Waveblade. What_Barnacles had posted a link for it. It's made in England I believe, when I first saw it I thought ok one more gimmicky device that will never work. I was wrong again. This thing is DC powered, a diver takes it over the side and works the hull. I was amazed, similar to that needle gun idea, and kept at the right angle it got all the barnacles and even removed many of the bases. I suppose because it was underwater it worked even better because the barnacles had no chance to "harden off". The thing costs about 300.00 and Jamestown Dist is where he picked it up. I'm sure there is a video on Youtube or somewhere out there. Entire hull was done in a day. He's gonna haul soon and do some touchup. If I'm around when he does I'll take some pics.