many people say that Goldfish will get huge, no matter what. i think otherwise. for five years i kept an Oranda (Lionhead?) pair together in a tank; the male (definately a male, he always got fishie-zits) grew to 3 inches, the female grew to 2. sadly, the boy was claimed by my cat as dinner and the female to my brother overfeeding her.
i'm retrying with a Calico Fantail/Black Moor pair now, the fancier and much less identical fishies. i'm beginning to think Goldfish have a mechanism that allows them to not grow that large unless space and food are available; because while Bug lived in a bowl it tooks six months for him to gain a quarter-inch in length, but in the two weeks he spent in the 50 he gained 10 pounds! (i exaggerate, but he definately grew from 1.25 inches to around 2)
just keep them on Goldie-diets, and make sure if they do get big you find them good homes. i'm probably wrong, but hey- i'm fourteen! i'm allowed to be a smart-assed kid
adding for OPCN: Goldfish are neither deformed, crippled, nor unhappy. messy, yes, but all pets are messy and are fish not pets? i think the most deformed of Goldies are Celestial Eyes, because they're eyes are seriously messed up, otherwise Goldies are happy and healthy little fish with as much spunk as any other fish. any fish will be unhappy in a tiny bowl, and will become crippled without proper space or food. so if you've ever had a deformed, crippled and unhappy Lionhead- it's your fault. -nods sagely-