My husband and I bought combo tickets to the zoo and the aquarium (60 euros altogether), and after…read morethree hours enjoying the zoo, I wasn't sure that I had the stamina to tour the aquarium. I'm so glad that I powered through, because it was even better than the zoo! My husband does not speak or read any German, and my competency is slightly above elementary, but we found that more of the signage at the aquarium is in both English and German than the signage in the zoo. Even though the name clearly reads "tropics/aquarium," I was expecting to see only water creatures. Wrong: this is where the lemurs and lizards and snakes live, too! I was expecting to see the lemurs in the zoo portion, but no, they are the first exhibit one encounters in the "tropics/aquarium" part.
I loved the design of the space: the maze-like way one moves from exhibit to exhibit, the seemingly hand-written and hand-drawn signs, and the neat way that the environs of the smaller animals are presented in wooden cabinets as in the Renaissance cabinet of curiosities. Imagine an aquarium and zoo presented in a venue like Sir John Sloane's Museum in London, and that's very close to what one encounters here.
If we had been pressed for time and could have only done one venue, I would choose here over the actual zoo, it's so good.