I can't recall whether I've posted these shots before. Otter Cove, Pacific Grove, CA: 2006, I'm fairly sure.
These shots demonstrate how you can have both poor and fine visibility at the same time in Monterey Bay. You just have to be willing to keep your focus on what's within an arm's reach.
And, you'd better have that arm reaching out as you swim towards the bottom, that or fast reflexes in gear as that bottom suddenly appears seemingly from nowhere. While a rocky bottom may seem more dangerous in such conditions, the sandy bottom is actually harder to discriminate from the general low-viz blur . . . . The face mask will shield your nose, however, in the case of an actual collision.