Direct answer
Yes. Hippos are commonly observed in pools and wetland areas throughout the crater.
Recommended Tanzania safari tours
1 Day Tarangire National Park Safari (Tanzania)
You visit: Tanzania
Tanzania · Day trip elephant country
12 Days Tanzania Luxury Safari & Zanzibar Beach Holiday
You visit: Tanzania, Zanzibar
Tanzania · Northern circuit + beach
3 Days Serengeti & Ngorongoro Crater Safari (Tanzania)
You visit: Tanzania
Tanzania · Crater floor & migration country
3 Days Serengeti National Park Safari (Tanzania)
You visit: Tanzania
Tanzania · Plains wildlife focus
3 Days Tarangire & Ngorongoro Crater Safari (Tanzania)
You visit: Tanzania
Tanzania · Baobabs & crater
4 Days Tanzania Wildlife Safari
You visit: Tanzania
Tanzania · Compact northern loop