What episode is the collection of beautiful crystals?

This is episode 29 of season 3.

It was called by Mo Mo.

Momo, jealous that Matsuzaka likes the south wind, thinks he just needs to grow up, so he buys goods that can grow up quickly in the magic shop. Although she finally grew up, she became a frog and Yamei became a tadpole because of side effects. Finally, in the magic shop, there is only one antidote that can make a person return to normal. DOG gave this opportunity to Yami. At this moment, a lotus in the pond is shining, DOG is shrouded in red light, and Matsuzaka and Murumo collect crystals to make DOG return to normal.

Because Momo's kindness makes the crystal shine, it is also a kind of crystal, so it is named beautiful crystal.