Diamond: It has a flotation sac that is like an inflatable collar. It floats on water with its head out.Pearl: It swims by rotating its two tails like a screw. When it dives, its flotation sac collapses.Platinum: It spins its two tails like a screw to propel itself through water. The tails also slice clinging seaweed.
Gender Differences: Male has two white spots on his back while female has one