Wide Angle Underwater

Most UW WA falls into few types

1- close subject (diver, large critter) with an expansive background.  The fisheye is esp successful here - just get the subject in the center 50% before the curvature distortion matters.   Your strobes are set for the subject, but your overall exposure for the background.

2- close range shot of wider target (reef, really big fish or wreck).   Fisheyes are good for the fish/reef, not always so for the wrecks, though again if you can position the bulk towards the center, still works fine.

3- but there's also WA macro where you get the camera within inches, or just a couple feet away, and with it can get great lighting.   At 35mm or longer, you're giving up on subject coverage or effective flash.

4- true open water WA, where nothing is within strobe range, can be the most difficult to get a color balanced result, even in the tropics.  If you're not shallow, you have little but blues and greens.   Going B&W is one way to address.    But WB concerns aside, as you note, it can be difficult to show a clear subject.

I saw in my mailbox that Backscatter is doing a couple WA seminars on Roatan, a place you frequent.   Worth checking out.   But you should also look into a fisheye lens/port combo.

True WA - fairly success, though still on the blue side.  Fish school migrations like this are good subject.

I like the composition, but had to really doctor the settings aggressively, still not really happy with it.

just one or two xmas worms doesn't show the full rainbow

whole army of banded shrimp

full color from the short range (likely < 1ft)

A cooperative dive-model gives lots of shots, including the sun silloutte.  Again, actual range is just a couple feet, else it would be difficult to line up.

sharks can do the same shots as divers, but slightly less cooperative models.  Have to predict their path, or just be quick.   But with shyer sharks, the fisheye like this 8mm just means tiny looking sharks.

Tiger beach is of course nothing but WA.  The challenge here is to capture the size of the tigers effectively, which requires nearby divers.