Not necessarily, but it is your choice. It is a waterpark and you would figure it would be enforced but not really. However you feel comfortable
Per the rules, officially you have to wear a bathing suit, BUT the rules didnt seem to be too enforced while I visited less than a month ago. I saw people in Jean shorts and even pants, but they weren't in the water. I would wear a bathing suit or at least bring one to be safe
You can wear anything you are comfortable in.
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