The staff are friendly and very helpful.
We can also interact with certain animals, but for "feeding" it can't be arbitrary and there is an additional fee, but it's quite affordable.
Rides like the River-Boat are also quite interesting to try, the additional fee is around IDR 30,000 / person when I come.
And it is highly recommended to take part in the Animal Show, very interesting. Yesterday's schedule I joined the show at 11.00.