At several major pet store chains across the United States, betta fish are sold one to a container, sitting on store shelves in small plastic cups. More than 50 veterinarians, scientists and fish welfare professionals have now signed an open letter calling for these cup displays to end.

The experts’ concerns are specific. According to the letter, cups this small keep bettas from acting like healthy fish and allow toxic ammonia to collect in the water. Without good filtration and steady heat, the fish can end up living with ongoing stress and illness.

The End Betta Cups campaign, led by the group Betta World For Bettas, is asking Petco, PetSmart, Pet Supplies Plus and Pet Supermarket to make a public promise to phase out cups and to share a clear timeline for it by March 2027. The fix is straightforward: move bettas into heated, filtered tanks, or stop selling them. According to the campaign’s founder, independent shops already house bettas without cups, and large national chains have the means to do the same.

“Seeing sick and dying betta fish in cups should not be accepted as a normal part of visiting a pet store,” Ariel Heinicke, founder of Betta World For Bettas, told Lady Freethinker.

The people who study and care for these animals for a living have spoken clearly: the cups need to go. Petco, PetSmart, Pet Supplies Plus and Pet Supermarket can follow the science and set a firm deadline for change.

Sign the petition to tell these four retailers to end betta cup displays and commit to a plan by March 2027, while the experts’ warning is still fresh.