Hal - Neon - Hemigrammus rodwayi (Golden tetra)
The Golden Tetra Hemigrammus rodwayi is a pretty little characin. Its gold appearance is due to a specialized layer on its skin that defends it against a trematode parasite. This fish is more prone to disease, especially skin parasites, than many tetras. The gold color comes from 'guanin,' which is secreted by its skin to protect it against these parasites. This makes it look like it has been covered with gold dust, thus its name. It is also known as the Gold Tetra and Brass Tetra.