It costs 50,000 rupiah per person and you are not allowed to take any food or drinks in. They have a restaurant serving pretty basic food like nasi goreng and mie goreng. I would suggest eating before you go.
If you have been to Water Bom in Kuta and are expecting something similar, you will likely be disappointed. It is more suitable for toddlers and young teenagers.
Like Waterbom you have to pay extra for the gazebos. Unfortunately there are too many other places to sit and relax. Even though the park was pretty quiet, most of the seats were already taken. It is just new, so I hope the facilities will improve in the future.