Role in series
"Chum Bucket Supreme"
When Patrick's head is set on fire from mass confusion, Plankton urges him to use the kelp juice that he is drinking to put it out. Patrick ignores this warning and offers him a sip of the drink. Fed up with his stupidity, Plankton snatches the cup out of Patrick's hand and throws its contents over Patrick's head to put out the fire.
"Squid Plus One"
Squidward tries to relax at home by pouring himself a glass of sparkling kelp juice.
"Stuck on the Roof"
Squidward prepares a dinner for himself at home. He pours two glasses of kelp juice, clinks them together, then drinks them sequentially.