Spend a day visiting the different bays around Koh Tao on a snorkeling trip, one of the best ways to see Koh Tao.
DJL now offer their own snorkelling trips wich are run either off their own snorkel boat or during the low season from the main diving boat. The trip costs the same as the other snorkel tours, however with DJL you also get your own Divemaster to guide you round the snorkel sites and identify the aquatic life.