Cleaning the anchor.
Sometimes the anchor brings up large lumps of mud when it is raised.
Instead of spending a lot of time trying to knock it off or scrubbing it, try reversing fairly fast with the anchor just below the surface.
The flow of water past the anchor will probably clean the worst of the mud off and there is little risk of damaging the boat with the anchor. You will still need to clean off the residue but you will not have large lumps of mud on the deck.
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