The Marine Patrol do not have a problem with bleach bottles that are placed in an area to be helpful. Naturally they reserve the right to remove them if they don't like the placement.
I think what would work here is to find an old busted in half boat and secure it up on the rocks. That might give boaters a visual indication of which side of the markers they should be on.
Then you could have a cute name for the area like "Hole in Boat Bay" or "Propeller Pile Cove". I was sailing the coast of Antarctica when we came on a large dangerous rock. The chart actually had it's name "Full Astern Rock".
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