Catching Some Z's: Walter the Penguin will do that after using his ability several times.Cat Smile: The Star Catcher sports an adorable one.

As a result, rather than chomping on your named guppies, your carnivores feed on the nameless guppies that can be released any time at no cost.

In the Virtual Tank, it is mentioned that store-bought pets will not eat each other.

Also averted with Gash, who happily chomps on one of your guppies from time to time.

Averted with carnivores, guppycrunchers, and ultravores, as they survive on guppies (the first two) and carnivores (the latter).

Bread, Eggs, Breaded Eggs: Stanley, one of the bonus pets, is afraid of nothing but badgers, aprons and badgers wearing aprons.

Bioluminescence is Cool: Gumbo the anglerfish, or at any rate his (Yes, his) esca.

Also, the bioluminescence of a deep-sea anglerfish's esca is due to bacteria it cannot be switched on or off.

Artistic License Animal Care: Gumbo is a deep-sea anglerfish (illuminated esca rather than one which looks like a worm) and could not survive anywhere near the surface, much less in an aquarium.

Same can also happen if all guppies turn into Nostradamus and no other fishes are present in the tank.

If Amp electrocutes guppies and no other fishes are in the tank, the game will give the player a free baby guppy instead of losing the level due to not having any fish in the tank (just like Tank 1-1 in Adventure Mode for the first time if all of the player's fishes were dead).

The hunger timer will pause during an alien attack, so you won't have to worry about fish starving while you can't feed them.

Lampshaded with Stanley the Startlingly Small Sea-Serpent.

Animals Not to Scale: Because all of the pets are roughly the same size, some pets can be really small compared to the animal they're based on, like Wadsworth the Whale and Brinkley the Elephant.

There's also Stinky, a male snail that wants to impress the ladies despite snails being hermaphrodites.

Animal Gender-Bender: Gumbo is mentioned as male, but the illuminated esca is a feature that only appears on female anglerfish.

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