Dale. While you are correct about the tropic and coral. We have little coral in the cold waters of the PacificNW. Also very few bikini wearing boaters, which I blame on the cold water.
We do have the Fraser River and it brings gobs of glaciers silt into the waters. This has been deposited all over the vast basin that is the Strait of Georgia. There are patches with nice kelp beds. There is a lot of mud, and even some places with pebbles on the bottom. Rarely in the traditional anchorages with you find large rocks that could cut your rode. It is possible.
We do have serious tidal currents that change direction and then run. You need to sink your anchor in deep and when the tide changes direction check that the reset has happened. The right anchor set is aided by chain ( I carry 105ft) but that is mostly to have the anchor as close to the bottom as possible when the tide changes direction. Close to the bottom the anchor resets more quickly.
If your using mostly rode (line) you can accomplish the same with a Kellet. It would be a whole lot lighter to use and retrieve manually. Here are some examples. You would retrieve the kellet first up the rode, then haul up the rode and anchor.