8 Top Reef-Safe Sand Sifters

Conchs

The tiger sand conch (Strombus sp.) is popular. They spend all their time cleaning and aerating the sand bed and may even disappear into the substrate for months. Completely reef-safe, they do not harm beneficial sand microfauna or disturb the beneficial bacterial zones in the sand layers.

While performing their roles as scavengers and sand sifters, they are also entertaining to watch as they move through the sediments. Adaptable, hardy, and friendly to tankmates, just a few conchs can positively impact the health and appearance of an aquarium substrate.

Hermit crabs

Hermit crabs are excellent sand-stirring invertebrates. Reef-safe hermit crabs spend all their time searching for and eating algae and detritus. Smaller species of hermit crabs are preferred over larger ones, as they are less likely to disrupt the tank environment when dragging their large, heavy shells along the bottom and reef surface.

Red Goatfish

Red Goatfish Docile Goatfishes, particularly the red goatfish, are among the most charismatic sand sifters. They dig, shovel, and blow sand while searching for invertebrates like small worms. Goatfish have beard-like appendages called barbels, both long and short, on their lower lip used to taste the sand for food. You might need to replace some sand they displace as they act somewhat like a leaf blower!

Sea Stars

Sand-sifting sea stars (starfish) are exceptionally reef-safe and only benefit your tank. Every marine tank should have one of these long-lived, beautiful creatures. Sand-sifting sea stars typically come from one of two genera of the class Asteroidea (starfish).

Astropecten polyacanthus are most common and excellent sand bed cleaners, but they can be too efficient! Some reef enthusiasts avoid them as they might strip the sand of beneficial bacteria needed for biofiltration. Thus, it's not wise to place them in a small or new "clean" aquarium, where they may starve.

Sea Cucumbers

Segmented into five body parts like their attractive cousins, the starfish, "caterpillar-like" sea cucumbers are arguably the least visually appealing animals you can put in a saltwater aquarium. Yet, many of these species do an excellent job cleaning the sand surface as they move at a slow pace. Sea cucumbers will consume detritus and uneaten food and may also eat snails and other sand-dwelling critters, so monitor them closely.

Crabs

Most marine crabs are known for their voracious appetites, consuming detritus, uneaten food, and carrion in saltwater aquariums. Unfortunately, many crabs will also eat just about anything else in your tank, including healthy corals, invertebrates, and fish.

However, some reef-safe crabs do not consume the "good" animals in your reef tank. Still, be cautious when placing crabs. Even with "safe" species, you may occasionally encounter one that does not leave corals or invertebrates alone.

Gobies

Gobies are among the most beautiful and entertaining fish in saltwater aquariums. Some gobies process the sand substrate in search of algae and detritus. Sand-sifting gobies literally chew the sand to remove food particles, then either spit the sand out of their mouths or eject it backward through their gills.

Snails

Different snail species prefer different types of food, such as diatom films, plant-like algae, worms, and detritus. Understanding your tank's needs will help you choose the best snails.

Rock-dwelling snails spend their time on rocks in a saltwater aquarium or glass, avoiding sandy bottoms, which are hazardous. These snails cannot extend their foot far enough from their shell to turn themselves over if on their backs.

However, some reef-safe sand-sifting snails can flip over to avoid starvation and predation, consuming detritus and algae in your sandy substrate. The Nassarius snail even descends into the sand bed with only its snorkel protruding, keeping the sand stirred.