The Octonauts and the Little Mermaid

The Octonauts and the Little Mermaid is the 20th episode of Season 1.

Summary
When Kwazii and Dashi meet Ariel the little mermaid, they tried to convince Captain Barnacles, who doesn't believe in mermaids, that mermaids do exist. But when Kwazii senses that Atlantica is in danger,he and the Octonauts come to the rescue. After the big save, Triton, Ariel's father, awards Kwazii with a special ocean pearl bracelet.

Plot
The episode starts in the Octopod with Kwazii playing table tennis with Dashi and Inkling when he sees a blurr of red, green, skin peach, and ruby red pass by which had him distracted from the game and he and Dashi go to the window to see what it was, but it disappeared. So they go outside to find the creature who swam to the coral filled with treasure and lost things.