Bottom Cleaning and Pressure Washer

[four winns 214]

I have rented a slip for the summer. The bottom on my Four Winns 214 is not painted. The marina is just off the Ohio River and the bottoms of boats left in the water get gnarly pretty quickly. I intend to pull the boat every week or ten days and clean the bottom. I will also pull the boat and leave it out of the water if it appears my schedule or weather will not allow boating for more than five days or so.

Is it possible to safely use a pressure washer on the bottom? If not, what's the next best way to clean the bottom?