If left untended and unmoving.
Believe it or not, sailing the boat (or anchoring where the tidal current
is at least 2-3 knots at peak) will **significantly** extend the time you
can go without starting a hanging garden/barnacle factory. Long ago
(before Micron CSC), I had Ursa Minor in a slip in the Gulf Intracoastal
Waterway, where diurnal tides generate a peak current of about 2 knots. I
waxed the bottom before launching. It took almost 6 weeks before a lot of
growth showed up -- in the summer, no less.
I'vee also sailed the Keys for 5 weeks without bottom paint, with
essentially no growth ... but we were sailing every day.
Regards,
Bill Combs
WWP 19 #439, "Ursa Minor"
Fort Walton Beach, FL
ttursine@gnt.net