I don't want to turn a thread about bottom paint into a discussion of hull cleaning, but a number of posters so far have discussed hull scraping/pressure-washing, so here goes: My hull received two coats of bottom paint (brand unknown, but done at a very reputable yard) in 2012. The paint is black, if that helps? The boat is in Prince William Sound, in Southcentral Alaska.
As a diver, in 2013 I took a deck brush down to remove some of the green scum that accumulated over the winter and found that even gentle brushing would release clouds of black "dust" into the water. This appears to be a surface layer of oxidized paint--there is no chipping or other signs that the paint had failed mechanically to attach to the hull.
My question is whether it is better to leave the green scum *and* all the paint where it is, rather than lose some of the paint through the brushing process? Or is a clean bottom always a "happier" bottom, as long as the bottom paint is not wearing visibly thin?
This is my first boat with anti-fouling paint. As a diver, I can give it all the care it needs below the waterline, but a haul-out will be much more difficult and I'd like to delay it a few years, if possible. Thanks in advance for any insight or suggestions!