Why not coat the prop with a highly radioactive substance. That will kill
whatever wants to grow and the water would acts as shielding so the
radiation wouldn't travel far.

Amen!

wrote in message
oups.com...
Around here, I have to dive and clean my prop at least 4 times a year
due to fast fouling. If I didnt use her much I'd have to do it more.
Like many other people I have noticed the fact that boats that are used
more have cleaner props.
So...........I propose a device which simply spins your prop several
times a week to minimize fouling. It'd be something like a small motor
driving a belt going around the shaft. You'd have to leave her in
neutral for this to work. Something like 30 secs of prop spinning
every other day might really reduce fouling.