According to PetSmart's website, a betta fish tank should hold a minimum of 3 to 5 gallons of water. Petco spokeswoman Ventura Olvera did not respond to messages for comment.

The claim: A faulty Petco aquarium heater caused a fire at Medtronic’s Columbia Heights campus in 2007, resulting in more than $1 million in property damage and lost business.

Petco earns most of its revenue through the sale of pet supplies, like aquariums, bird cages and food, but it does sell some small animals like birds, reptiles and fish.