Advice/tips for taking a 4 year old?

[Happyinwonerland]

We have been daydreaming of Discovery Cove for a few years now. I think I'm going to try and take the family this fall, maybe towards mid to late October. DD will have just turned 4 when we go. I'm torn between thinking she will love it and thinking she will be terrified of swimming with the fish and other sealife.
Anyone ever been with a 4 year old? Advice, tips, wisdom to impart? Thanks!