Invisibility

Invisibility is a power that all Aquitarians and Hybrids are shown to have. However, it appears that only natural born Aquitarians have this power. Heather Merrill and her sister, Hayley Hale have the ability because they are Hybrids. There is also a possibility that Hybrid has simply not "unlocked" this power until they were older. With this power, it allows the user to stay invisible, but it is only temporary.

The user puts their hand in a fist motion and turns invisible. It seems like the merpeople is enveloped in a water bubble, which makes the user invisible. Merpeople are capable of staying invisible with legs or tails, in or out of water. Rita Santos is the only mermaid that seems to be able to use her powers to see invisible merpeople by using a hand motion, as it was shown when she sees Zac Blakely in her office after he stole the test.