Our first night on the Big Island we did a manta dive. A synopsis: descend to 35 feet, hold up flashlight which excites plankton, mantas feed on plankton. There were at least six, perhaps eight, rays that night. Very cool; we bought the video from our excursion. Remind us to show it to you. There's a fascinating eel incident on it as well... We really enjoyed Big Island Divers. I recommend them if you head out that way.