E.C.
Yes you can per their site found here:http://www.seaworld.com/SitePage.aspx?PageID=113
May I bring my own food and beverages into SeaWorld San Antonio?
SeaWorld San Antonio has a strict food and beverage policy as to what may or may not enter the park. Below is a list of what is, or is not allowed under the food and beverage policy. If at any time you have a question about items, please speak to a supervisor or Guest Services.
IS ALLOWED:
Small ice chests of six-pack size or smaller (one per family).
Special dietary food, diabetic, health related or dietary needs. These types of specialty foods may enter the park with park management approval.
Baby food, bottles, jars and other baby items.
Fountain drinks, single serve drinks, refillable mugs (if opened prior to turnstile).
Reasonable quantity of bottled drinking water. Juice boxes (straws must be disposed of).
Single servings of snacks.
IS NOT ALLOWED:
Alcohol is never permitted in through or out of the turnstiles. Any alcohol from outside of SeaWorld must be disposed of prior to entry. Any alcoholic beverage purchased at SeaWorld must be disposed of prior to exiting through the gates.
Ice chests larger than six-pack size.
Straws and lids.
Bags of fast food items, picnic baskets, sandwiches or loafs of bread (meals).
Soda, sports drinks or energy drinks (single serving is allowed if open).
Large servings of snacks.