The third version of Snowball was a male cat named Snowball III and was killed when he drowned after he tried to catch a goldfish in the aquarium while Lisa was in the kitchen preparing his cat food for the first time . She passes over a skunk , a siamese cat , and a cat with an eye infection before finally deciding upon Snowball III . He drowns trying to catch a goldfish in an aquarium while Lisa is preparing his cat food in the kitchen for the first time .