On the print in they inform us that at some point in the future they are looking to bring back common hippo. It is at the start of the video streamline!
Yes, the zoo made a comment about obtaining more hippos in the future, which I suspect was a throwaway comment in the wake of Faith’s death. The hippos were crowd favourites and hearing that the zoo may get more hippos one day would have gone down better than “We have no intention of ever replacing them.” In short, Common hippopotami are not well suited to a city zoo; and the effluent run off is immense, which makes keeping the pool clean expensive and a challenge. I’m not aware of plans to import Pygmy hippos, but I agree with Zorro it was the logical thing to do with the exhibit in 2016. That chance has now been missed.