Our dives when like this..
First dive in the water at 10:30, sea's almost flat calm, temp 87 at depth, vis 15 to 20 feet (we where in 28 feet of water)
Second dive in the water at 12:30, sea's almost flat calm but picking up a bit with an onshore breeze, temp 87 at depth, vis 15 to 20
Last dive after lunch, in the water at 2:30, sea's 1 to 2 feet, on shore breeze 5 to 10 knots, temp 87 at depth, vis 10 to 15 at depth 5 to 10 on surface.
As far as anchoring is concerned, with a fluke type anchor you MUST let out lots of rope otherwise it will not dig into the sand and a mushroom type anchor does not work in sand. I usually drop anchor, let out at least twice the distance in rope as there is depth (i.e. 30 feet deep = 60 feet of rope) after that I will back the boat up down current from the anchor to set it. Dive down the rope and check it and help it along if necessary.
Just my H2O