Chinese Algae Eater (Gyrinocheilus aymonieri)

Don't let the name and the juvenile behavior fool you: young Chinese algae eaters are diligent glass-and-driftwood scrapers, but as they mature past a few inches they shift diet and temperament both, turning territorial and switching from algae to slime-coat rasping on slower tankmates. It's a classic bait-and-switch fish — great in a young community tank, a liability once it's grown up.

Care level: Moderate · Temperament: Becomes territorial with age · Max size: ~10" · Min tank: 30 gal · Diet: Omnivore, algae as juvenile, more carnivorous as adult