Manny's goldfish

Manny's Goldfish was the fish Manny bought in the online version, but in Dog Days, he bought fish food.

Online Version
In the online version after Greg's birthday, Charlie Heffley took them to buy pets. Rodrick was buying a snake, while Greg and Manny bought fishes, but Susan told Rodrick it was dangerous and forbade him. So Rodrick took an aggressive fish while Greg got an Angelfish and Manny got a goldfish. Rodrick's Fish ate Manny's Goldfish shortly afterward and attacked Greg's at the same time.