Thought I would share an underwater scooter I stumbled upon while diving in Key Largo recently.
It mounts on the back of a dive tank, is lightweight, and the small control trigger can be held alongside your camera handles allowing easy access to camera controls (Vs. attaching the camera to the scooter).
Should work well for keeping up with those fast moving subjects i.e. dolphins and sailfish, which is what I plan on using it for.
Mike