Lilo & Stitch: The Series - Season 1 - Eps 15: Tank
The Hula Girls have ditched Mertle for Lilo, and consequently, Lilo neglects Stitch to hang with them at the Kauai Medieval Festival. So, when Experiment #586 is activated, Stitch needs someone to capture it with. And who does he team up with? Mertle. Strangely, Stitch and Mertle are having fun trying to capture the metal eater, but this ends when it storms the Medieval Festival.
About Lilo & Stitch: The Series

Title: Lilo & Stitch: The Series
First Air Date: 2003-09-20
Last Air Date: 2006-07-29
Status: Ended
Rating: 7.38/10 (from 576 votes)
Language: EN
Seasons: 2
Total Episodes: 67
Network: ABC Disney Channel
Genres: Animation, Family, Comedy, Action & Adventure, Sci-Fi & Fantasy, Kids
Production Companies: Disney Television Animation
Synopsis
This animated series chronicles the further adventures of renegade scientist Dr. Jumba Jookiba's beloved Experiment 626, who is now living happily as Lilo's alien buddy Stitch. Jumba’s remaining experiments have landed all over Hawaii in the form of dehydrated pods. Lilo and Stitch’s mission is to catch Stitch’s "cousins" before they fall into the clutches of the evil Dr. Jacques von Hamsterviel!
Cast

Daveigh Chase
Lilo Pelekai (voice)

Chris Sanders
Stitch (voice)

David Ogden Stiers
Dr. Jumba Jookiba (voice)

Kevin McDonald
Pleakley (voice)

Tia Carrere
Nani Pelekai (voice)

Kevin Michael Richardson
Captain Gantu (voice)