I agree with all of the above.
My boat sat most of last summer. Early Oct. I took a trip of a few days just to get away and have time to myself. It 60 miles each way. I saw the fuzz"s at the water
line. When I backed her out of the slip she felt heavy like I never felt her before. I got her under sail, as each hour went by I was picking up 1/10 th of knot. The bottom was polishing the growth off. On the way back i had pick up over a knot to knot and half just by getting the boat moving.
A bottom needs to move though the water to wash it's self clean.