If you can't afford the water park prices, you could always go downtown where the waterfront park is. There is a wonderful pineapple fountain the kids could dip there feet into. Also there is a big squirting fountain out front. There is no place to swim, but at least they could get wet and stay cool.
Another option you would have is NOT FREE, but would save you money. Try going to the Water Parks after 3 p.m. there is a discount given. Or they usually have a buy one get one FREE day, Tuesday, I think! Remember senior citizens get a discount, too.
We only stay at the Water Park for a few hours anyway. Who wants to get that much sun in one day? So, don't forget the sunscreen!
Rosey~