I just had my boat hauled and the bottom sand blasted for bottom painting. The Service Manager said my bottom was really fouled with "hair" growing out of it. I noticed a 6 mph and 500 rpm WOT reduction since I put the boat back in after my repairs in July. Do you Lake Michigan boaters experience this level of bottom fouling like I did this year on the Des Plaines River? I should also mention my bottom paint was on it's 5th season would could have been a contibutor. Also how frequently do you guys on the big pond bottom paint?