We discovered the water park about 3 years ago. Even though the ocean is only 1 block away, the water park allows you to use inner tubes to glide, slide and float around this wonderful park. The Jolly Roger offers different admission prices. I recommend a four hour pass. That is all you need. If the day is very sunny, expect waits at the rides.
The lazy river is great for adults, although I like the water slides too. I think you can take your own cooler, but if you can't, there is a concession stand.