Grow Up! Little Turtle (育てよ! カメ Sodateyo! Kame) is the sixth episode of Ultra Q.
A young boy named Taro develops a curious preoccupation with his pet turtle named Gameron, to whom he constantly encourages to grow. After getting into trouble for bringing his turtle to school and neglecting his studies, Taro winds up in the company of two bumbling gangsters as they flee from the authorities. While hiding out in the sewer, Taro is delighted to find that his turtle has suddenly grown to 99 cm in length. The sight of the giant turtle, however, frightens the gangsters into the welcoming arms of the police. Assuming that Taro had been kidnapped by the two thieves, the authorities return to collect the boy, who is nowhere to be found. Instead, he rides on the back of his turtle to the undersea Dragon Palace, as depicted in his crayon drawings. There he meets a young mischievous princess names Otohime, who eludes Taro while riding on a rocket and then proceeds to sic her pet dragon named Kai Dragon on him. When Taro wishes to return home, Otohime gives him a mysterious box, which she tells him never to open and he is immediately transported back to his family. Unable to resist temptation, Taro opens the box and instantly becomes an old man!
- Ultra Q Volume 2 features episodes 5-8, while the Total Natural Color Blu-Ray Volume 2 features episodes 4-7.