As you can see from our pictures, the Black Garden Eel (Heteroconger perissodon) is often not black in colour. Some individuals are light grey or tan. It is believed that the type and colour of the sand that is the eel's environment has an effect on the colour of the eel. These are mostly found in central and eatstern Indonesia and The Philippines. Like all sepcies of Garden Eels, they hide most of their bodies' length in the sand, and live in groups. When they feel safe enough, the extend their upper body to reach out into the current and collect plankton as food. As soon as any threat gets close enough the whole group will descend back into their sand holes.