Re: Sacrificial Anode for Jet Pumps?
Merc Sportjets (and bigger jet pumps) all come with an assortment of anodes from the factory. There are 4 on my sportjet that I can think of offhand. (reverse bucket, 2 on steering nozzle, 1 big one on the main pump)
As far as PWC's, seadoo has an optional kit for any pwc/jet boat meant for saltwater use.