They have a lot of tropical fish, inverts (like the upside-down jellies pictured above), and, of course, a seahorse breeding program. Like most aquariums, they also have a touch tank, one for rays and one for inverts, which holds horseshoe crabs and conches among other things.
Across the street, in another building you have the rehabilitation center. Here you can check out some critters who are being fixed up for re-release, and some who are permanent residents. When I went, they had some turtle hatchlings which were very cute, but hard to take a picture of because they were so active! The rehabilitation center has a lot of signage posted about the animals that they have, and what particular ailment brought them there.
The aquarium portion is a medium-sized facility, which could capitalize on the research aspect more. They do have some signage talking about what research they do, especially for the sea horses and shark tagging, but you don't really get to see what's going on. The price is a bit pricey at $17 for adults and $12 for kids, however they are AZA, so if you have a membership to another AZA institution you may be able to get in for free or half off.
Is it worth the price of admission? YES!
Did I forget to mention that they have the only giant squid displayed in the USA...