Aquariums

Here's a habitat in with some sea slugs. It costs 100 diamonds and it cannot be traded for, so...that sucks.

Enrichment items often look different in the aquarium, terrarium & bird house, depending on the animal in the exhibit.

The lobster, nautilus and jellyfish are special 1000-diamond bonus items: you can only get them by buying 1000 diamonds. I know!