Me before the Option was added to turn Lights on during Day: every Roof is totally overrated except it's completely or almost completely made out of GlassRoofs are overrated.
Made a (second) habitat for the hippo's. It's ended up being a pretty huge area. Now I was wondering if there are any animals that can safely life with them.
Now doing some foilage around the paths so the guests can't look into the great emptyness.
Sadly Frontier didn't make their territorial Behavior realistic, so almost everything can live safe with them in the Game. The only Species I know of so far that gets attacked by them, is the Indian Rhinoceros. You might try keeping Flamingos or Nile Monitors with them (but not both. Tried to keep both Species together in a Career Mode Zoo and it didn't end well).
You could also try to keep Gharials with them if you don't mind keeping Animals from separate Continents together. They can be even kept with Flamingos due to their strong Adaptions to eating Fish and small Animals