gina, not sure where you will be staying, but know that there are THREE "aquariums" in the dallas metro area.
1. Children's Aquarium at Fair Park [about 2.5 miles east of downtown but accessible via the DART Green Line] - it's been updated but still an older venue and more geared for kids.
http://www.childrensaquariumfairpark.com/index.html
2. Dallas World Aquarium - downtown at 1801 N Griffin St Dallas, TX 75202.
it has a cool "tropical aviary/waterfall/pool" area, some standard tanks w/ sealife from around the world, a shark tank, penguins, a Mayan area, ets. kinda pricey at around $21 but a great place.
http://www.dwazoo.com/
3. SEA LIFE Grapevine Aquarium at Grapevine Mills, 3000 Grapevine Mills Pkwy, Grapevine, TX 76051. havent been but have not heard people raving about it. $20 but $5 discount if bought online.
https://www.visitsealife.com/grapevine/
if you like all forms of art, including a great new exhibit on Incan textiles & pottery, check out the Dallas Museum of Art downtown, just south of the Klyde Warren Park. good food in the Artium dining area, which has "Dallas Flowers" by Dale Chihuly.
https://www.dma.org/
across Harwood St down Flora St. is the Nasher Sculpture Garden [$10-15 fee] and the Crown Museum of Asian Art [free].
keep walking down Flora and see the largest arts district in the USA [in acreage, not necessarily in content] - symphony hall, opera/performing arts center, theatre, public arts center, Dallas public Arts Magnet high school.
btw, Klyde Warren Park is a green space between downtown and Uptown. tables & chairs, books/mags/newspapers, pingPong/foosball, and some food trucks. there is a restaurant on the north side of the park, but rather pricey. across the street on the north side is "Lark on the Park" restaurant. again pricey but very good.
enjoy your visit to "our fair city"!!!