The Spotted Garden Eel is unique from other eels (morays, snowflakes, etc.) in that it is 100% reef safe. A garden eel's diet is comprised of floating zooplankton brought to it by the water's current. The garden eel will always keep a part of its body inside the burrow even when feeding. If it cannot reach the food while also maintaining a "foot" in its burrow it will just simply let it pass by uneaten. For this reason the spotted garden eel is even compatible with the smallest of ornamental shrimps and you simply won't have to worry about the eel eating its neighbors. You will however have to worry about the eel's neighbors eating the eels due to their small size and docile nature. In the wild triggerfish are known for digging out garden eels right out of their burrow in pursuit of a meal (Shedd Aquarium 2011). For this reason I would avoid any aggressive fish-eating specimens as tank mates for your garden eels. A fish does not however need to have the potential to eat a garden eel to be an inappropriate tank mate. Big active fishes will spook the eels and force them to spend much of their time inside their burrows or with only their heads sticking out. This will prevent them from eating properly and cause them undue stress. A bigger tank will mitigate some of these problems with bigger active fishes. Even when initially bothered and scared by fish swimming in close proximity, the eels will eventually adjust to their presence and cease to retreat when a fish darts close to its burrow.