Probably weekend or during school vacation
Late spring till mid-fall
We were there mid November and it was empty. It was great.
This time of year we are not busy at all. Normally never lines and lots of good chairs
If you get there right at park opening in the morning you can also get a nice umbrella in a prime location at no charge, cabanas are little $$$.
We have been to Aquatica twice and it is never too crowded. Most people seem to come early afternoon.
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