There will be a Season 4 guys! , started filming this year
April and it is said to release in 2016
Saw this information on YouTube's official Mako Mermaids channel Aeon world
There will be 16 episodes
A new Chinese Mermaid Weilan played by Linda Ngo
Newer characters
All characters from Season 2 and 3 will return, however Erik and finally Sirena will not be returning :(
Mimmi is getting a love interest played by Taylor Glockner
Finally, an unconfirmed character of H2O Just Add Water will participate on Mako Mermaids
Even on the video it shows Chai (Zac) talking to the new Chinese Mermaid Linda Ngo
Season 4 preview summary
Weillan, a teenage Chinese mermaid releases a terrifying water dragon. She flees to Mako for sanctuary but the dragon follows. When the creature threatens the Gold Coast, the mermaids must find a way to destroy the dragon before it creates a chaos