B1 anode recommendation?? (90% fresh water)
 

What metal anode would I want to use for a boat that spends about 90-95% of its time in fresh water, and a few days a summer in salt? When I do go into salt, we go out and come back in through locks, so I always end up back in fresh water. Boat is used close to 300 hours a summer, but is stored on its trailer and not in the water. Every once in a while it will stay in the water over the weekend, but that happens maybe 3 or 4 times a summer for 2 nights max.
I assume zink anodes would be pointless for the amount of time I am in fresh, but is it better to go with magnesium or aluminum?

Magnesium is for fresh water, AL is for salt. I'd go with Mag myself do to the 90-95% use. But since it does not stay in water, not sure it would really make a difference.
300hrs use per summer= a lot of running time. Anodes don't work while the boat is moving. Does your boat have the Mercathode system?