Aluminum pumps pitting/ wet slip issues

[Skysurfer2010]

Last season I decided to wet slip my boat at a nearby marina. I have to say that it was the most fun I've had with my boat and I got way more use out of it. Unfortunately there is no ramp at the marina and taking the boat in and out isn't really possible without it being an entire day process. So the boat stayed in the water for about 6 months. I did use a brush and cleaned below the water line as often as possible. When I pulled the boat out at the end of the season things looked pretty ugly.

I tried cleaning the waterline down with JVs best and a 3000 psi power washer. It didn't work. I decided to put it away for the season and deal with it this season. I just dropped the boat off today at a detailer to remove the scum from the waterline down and put a fresh coat of Rejex on.

Now my issue has to do with the pumps. I cleaned them up as best as I could but I was left with a lot of pitting. It has the stock anodes. Should these be replaced with a different kind for use in fresh water? Is there anything I can do other than a lift to prevent more pitting from occurring?

I really want to wet slip again this season. I'm just worried that I'm going to harm the pumps more.