I came across this study from Osaka Metropolitan University today and I thought this would be the perfect place to share it.
https://www.omu.ac.jp/en/info/research-news/entry-23252.html
He loves to dig.
But he finally hit bottom.
He's been doing this for THREE DAYS:
I had to fill it in just to get him to start swimming again! But he's such an interesting creature.
Not relevant, I added this for no reason except that they're pretty!