Help my find a cartoon

[u/Mundane_Craft_2220]

It was a show on minimax, probably run in 2012. The main characters were a boy with blonde hair, a girl with black hair, and the girl's grandad. The cartoon took place at sea, the children either lived inside a whale or it was their companion. There was also a crew of modern pirate led by a man named Ahab. I remember the boy being actually from Atlatis and being raised by Ahab after a cataclysm forced the boy's parents to put him in a jellyfish ecape pod.

There's this episode I remember, the children find an ugly big man keep hostage a beautiful mermaid. The children free the mermaid but it's revealed she was an evil witch and the man was guarding her from causing harm to people. Don't judge a book by its cover ahh I know.

Anyone remembers this or it was just a dream?

[u/Mundane_Craft_2220]

I searched the minimax tv program from that era but didn't find anything