L.S.
I think it will depend on what you want to do there. Are you doing theme and water park or just water, just theme. If you plan on doing both it can be done in one day but you might feel rushed. But it can be done. Also depending on the weekend, if it's not a holiday or something like summer celebration going on you could probably not even book ahead and get a place that night if you wanted to stay. Another option is camping there is a camp ground next to the MIA. Hope this helps.