thanks for the note. It really has been great swimming here.
As for the waves, these are surface waves caused by wind, but not big enough to make me seasick at all. Although its windy, the reef stops the big ocean swells--inside the lagoon where I swim, it's fairly sheltered. And of course once I turn downwind it's pure fun, with the waves helping me surf along.
Depending on the tide, there are some currents, but mainly just over the coral flats where the water is shallow. There the water is squeezed into a narrow area between coral and the surface, so it has to speed up. It can be fast enough that I can barely make any progress--my own endless pool!
In the deeper water inside the reef, the currents are much less noticeable--yes, it can slow you down a little (or make you faster), but nothing dangerous that wants to drag you offshore. So I usually swim there--though of course it's fun sometimes to swim over the coral flats, too. But not at low tide--then you'd have to walk, as the flats dry out completely.
Luckily the sharks have all been very shy so far! But it is neat to see them. The big aggressive sharks (tiger sharks) don't come into the lagoon--only nurse sharks and blacktip reef sharks--some as big as me, though, so it does feel a little scary to see them.