We went with 3 small kids on a weekday. It's a free place with no guides or anything- you just stroll through and out around their outdoor trail at your own pace. The inside really only had 5-10 tanks with fish in them, and the little ones weren't really interested in stopping to read the facts about the coastal bend. It's free, and a good way to spend an hour or so, but if you are looking for an actual aquarium that is better suited for kids, you need to try the Texas State Aquarium in Corpus Christi. (But its not free!)
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