Some of the species in the Shark Lagoon, like the blacktip reef and sandbar, always swim.
They have to move in order to get oxygen into their bodies through their gills. Other species in the Lagoon are ram ventilators–they can receive oxygen without moving. Examples of ram ventilators are zebra sharks, stingrays and freshwater sawfish. You might see these creatures laying on the ground at the bottom of the screen. There’s also a chance that you might not see them at all. Because of the location of the camera, the constant swimmers are more likely to move into the shot.