Nassarius snails, which are commonly found in the coastal zones of most oceans, are one of the most ideal scavengers and detritus eaters for a reef aquarium. They have oval, spiral shells that resemble olive pits, and vary in size depending upon species. The Super Tongan Nassarius Snail (Nassarius distortus), for example, can reach a length of up to 1 inch, and is larger, easier to see, and very helpful in larger aquariums. Smaller Nassarius snails, such as Nassarius vibex, are often around 1/2 inch in length, and are useful in smaller aquariums, refugiums, and aquariums with less sand surface area.

Nassarius snails have a long tube-like siphon that protrudes from the end of the shell. They spend most of their time buried in the sand, with only their siphon extending above the substrate. Because these snails have an incredible sense of smell, they quickly detect any food introduced into the aquarium, and cause the substrate to “boil” as they emerge in search of food. They quickly consume detritus, uneaten food, decaying organics, and fish waste before they can be broken down by bacteria and release excess nutrients in the system. In addition, while burying themselves they aerate the sand bed/substrate, which helps maintain adequate oxygen levels in the substrate.

The Super Nassarius Snail does best in an established aquarium with live rock and a deep sand bed. These snails are sensitive to high nitrate levels and copper-based medications.

The Super Nassarius Snail is extremely difficult to breed in captivity.

Supplemental feeding for the Nassarius snails is not required in a marine aquarium with an established sand bed. However, if insufficient food is present, supplement their diet with frozen meaty foods such as brine or mysis shrimp and pieces of fish or scallop.

aquariablog’s take: I have dozens of these in my tank. They do a fantastic job of keeping the sand stirred and eating detrius. It’s also fun to see all these little “periscope” like appendages sticking up out of the sand and then to see them absolutely erupt from the sandbed when I add food.