Invertebrates for Reef-Friendly Saltwater Aquariums

Hermit crab in shell. Dardanus megistos in aquarium

Invertebrates are not all "reef safe." Many of them will rip corals, eat fish, and otherwise devastate other tank residents. The invertebrates mentioned below are typically regarded as safe for reef tanks by experienced reef tank keepers. When it comes to living animals, keep in mind that nothing is infallible. Any species has renegades, so if your new tank critter doesn't work out, get rid of it before it does major harm.

  • 01 of 06


    Horseshoe crab

    Marine crabs are nearly entirely scavengers, consuming practically anything that comes their way, even living animals. Some crabs, on the other hand, are more selective eaters, eating uneaten food, debris, and decomposing items (such as dead fish), which might be advantageous in an aquarium.

    • Horseshoe crab (Limulus polyphemus)
    • Porcelain anemone crab (Neopetrolisthes ohshimai)
    • Emerald crab (Mithrax sculptus)
    • (Percnon planissimum)
  • 02 of 06

    Hermit Crabs

    Hermit crabs are the ocean's little scavengers. Many hermit crabs are picky eaters that won't eat just anything. Some, however, will consume the things you don't want in your tank, such as green hair algae, red slime algae, trash, uneaten food, and dead creatures.

    Hermit crab subtypes include:

    • Dwarf blue leg hermit crab (Clibanarius tricolor)
    • Dwarf red tip Hermit crab (Clibanarius sp.)
    • Dwarf yellow tip Hermit crab (Clibanarius sp.)
    • Dwarf zebra hermit crab (Calcinus laevimanus)
    • Electric blue hermit crab (Calcinus elegans)
    • Electric orange hermit crab (Calcinus sp.)
    • Halloween hermit crab (Ciliopagurus strigatus)
    • Scarlet reef hermit crab (Paguristes cadenati)
  • 03 of 06


    Many different types of may be found in saltwater aquariums. These shrimp are brightly colored and, for the most part, unharmful to the aquarium ecosystem. Many of these shrimps have a natural use in the aquarium by eating parasites (note: the Pacific cleaning shrimp eats parasites, while the Peppermint shrimp eats aptaisia), while others bring variety and are entertaining to watch.

    Shrimp subtypes include:

    • Coral banded shrimp (Stenopus hispidus)
    • Harlequin shrimp (Hymenocera picta or elegans)
    • Pacific cleaner shrimp (Lysmata amboinensis)
    • Pederson's anemone shrimp (Periclimenes pedersoni)
    • Peppermint shrimp (Lysmata wurdemanni)
  • 04 of 06


    Snails are fantastic scavengers, devouring trash, uneaten food, decomposing organics, and fish excrement. Many of these snails are excellent rock and glass cleaners, pulling algae from all surfaces as they go.

    Snail subtypes include:

    • Cerith snail (Cerithium atratum)
    • Nassarius snail (Nassarius sp.)
    • Nerite snail (Nerita sp.)
    • Pipipi snail (Nerita picea)
    • Star snail (Cerithium sp.)
    • Turbo snail (Astrea)
    Continue to 5 of 6 below.
  • 05 of 06


    In reef tanks, starfish are quite popular. Many of these animals, such as the Sand sifting sea star (Astropecten polycanthus) and the Chocolate chip starfish, are carnivorous and should not be kept in reef tanks.

    The following starfish are considered reef tank safe:

    • Brittle starfish (Ophiocoma erinaceus)
    • Serpent starfish
  • 06 of 06

    Flame Scallop

    The Flame Scallop is a reef-safe bivalve that poses no hazard to other saltwater aquarium inhabitants. It's a filter feeder that has to be fed floating micro-plankton to stay alive in the aquarium.