Aquarium enthusiasts are often on the lookout for colorful and exciting species that they can raise in their personal tanks. Rainbowfish are a broad category of fish that meet these requirements.

Unlike their larger counterparts, rainbow sharks are actually small freshwater fish that are perfect for many home aquariums. But — as their shark name implies — these fish have some ...

You can see right through this little aquarium fish from Thailand: Its skin is almost completely transparent. But when the light hits it just right, its body flickers with shimmering rainbow colors.

The ghost catfish’s see-through body caught the eye of physicist Qibin Zhao when he was in an aquarium store ... change in length as the fish swims, causing the rainbow colors to flicker.