The boxfish is aptly named for its box-like shape. Covered in a bony carapace, this fish has a square, rigid body that gives ...

Additionally, many deep-sea fish have eel-like body shapes, which helps make backward swimming possible. The backward-swimming deep-sea fish typically measured between 1 and 2 feet in length and ...

Judges and buyers pay attention to how healthy its skin looks, its size and body shape, and how gracefully the fish moves in the water. But the most important trait of all is the koi's coloring.