In my area of Nova Scotia we have two tides a day that average close to 2 m. or 6 ft. Also a seabreeze every afternoon that is often different than the night breeze. I have 150' of 3/8" BBB galv. chain on a SL 1500
windlass and NO swivel. Never had a problem. I do use a SS twist
shackle because my
anchor roller is quite narrow and won't accomodate a regular
anchor shackle (the pin jams). I suppose the SS promotes some rust in the first link of chain but I reckon I can just cut a link off if it becomes an issue.