The Acuario Interactivo Cancun is located in a shopping mall called La Isla. It is not very large and if you have been to Xcaret can be quite a disappointment. However, many local people and tourists go there because it in the so called hotel zone in Cancun, it can be seen in about an hour, and is much cheaper a visit than going all the way out to Xcaret.
As toto98 ´s photos show they actually have a sucessfull breeding program for dolphins.
Indeed, its quite disappointing after visiting Xcaret, although I would not consider it as lost time, since i saw New fish species and invertebrates.
I disliked the sealion exhibit