The east coast takes the full Atlantic swell and cannot be shore-dived, so it stays far less visited than the west. This operator runs Zodiac boat dives out of the fishermen's pier at Sorobon on Lac Bay to sites such as Turtle City, where turtles and eagle rays are the draw. Two-tank trips go in the morning and a single tank at midday. Bring your own gear.
Bookings go through the contact form on its website; it publishes no phone number or email address.