Will go along with all that Joey1 has said,
I do a lot in two estuary's,and the areas are stone covered and weed. and they do hold shrimp/sandeels do come over the areas looking for feed i think, as they tend to live in sandy areas. but have seen them burrow in small gully's of sand between the rocks, when i have watched them being trapped and feed on with bass and sewin.
Best times i have found, have been two hours ether side of low water.
patterns for me, have been shrimp/ sandeel patterns (use snakes flies for that) clousers all work well.

These are the snakes i use,

And the shrimp patterns
hope this helps,
Dai.
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