Mako Mermaids series 1

When fifteen year-old Zac goes camping on Mako Island, he has no idea his every move is being monitored by real-life mermaids Sirena, Nixie and Lyla, whose job it is to ward off trespassers. When he comes into contact with the magical waters of the Moon Pool on the night of a full moon, Zac is given a taste of Mako's powers, waking the next day to discover he has been granted fin-like feet and the power to control water…causing all sorts of trouble for Sirena, Nixie and Lyla.