Generally, no. Because Petco operates under strict corporate policies, most locations cannot offer store credit for "walk-in" fish.
Petco does not buy fish from individuals or local breeders. They work with large, corporate-approved wholesale vendors and cannot legally or logistically pay you for your fish—even if they are high-quality or rare. Can You Trade or Get Store Credit? does petco buy fish
While they won't pay you, many Petco locations will accept as a surrender. This is part of their Think Adoption First program. Generally, no
Whether you’ve suddenly realized your "baby" oscar is outgrowing its tank or you’ve successfully bred a batch of guppies , you might be looking for a place to offload your aquatic friends. If you’re wondering, the short answer is no, but they might still be able to help. The Short Answer: No, They Don't "Buy" This is part of their Think Adoption First program
Usually considered final sale and cannot be returned. "Think Adoption First": The Surrender Policy