Miss Helen, the 16-inch-long gray horn shark, was returned to the aquarium Monday night, two days after the heist was captured on surveillance video .
The footage shows two men and a woman carrying a child staking out an interactive touch tank at the aquarium for more than an hour on Saturday.
The video shows a man plucking the shark from the tank and carrying it away, off camera, still dripping water. Another man is then seen depositing a blanket-wrapped item into a stroller and walking off, accompanied by the first man and a woman carrying a child.
Police said the men put the shark into a bucket before placing it into the stroller. Authorities also said the suspects poured a bucket of bleach into the aquarium's cold water exhibit filtration system.
All of this appears to happen with at least two aquarium employees nearby.
SURVEILLANCE VIDEO: Bizarre shark heist in San Antonio
Miss Helen was recovered Monday night from a home filled with fish tanks and other marine life, said Leon Valley Police Chief Joseph Salvaggio.
Salvaggio said the men confessed to the theft, and investigators planned to talk with the woman on Tuesday. Salvaggio told San Antonio TV station KSAT that one of the men was knowledgeable about marine life and likely went to the aquarium specifically for that shark.
"The individual obviously had some knowledge on how to deal with these types of animals, we said that from the very beginning, otherwise why take it? And when we got into the garage and into the house, it looked like almost a mock-up of (the aquarium)," he said.
Authorities are speaking with the National Oceanic and Atmospheric Administration to determine whether any federal charges can be filed, Salvaggio said.
KTRK-TV and the Associated Press contributed to this report.