Good Guys

Fist thing to know, these guys are good guys & should be left in your aquarium.

Stomatella snails are one of the creatures I see people asking for identification for nearly every week! They are a snail that looks like a slug or a snail with half of a shell. Their shell covers half of their body, and their head, the shell is a similar shape to a finger nail/oval shape.

Stomatella Snails are a valued member of your reefs clean up crew. They are great algae eaters and will help combat undesirable algae within your aquarium.

Stomatella snails grow to be about 2.5 cm and come in a variety of shades between white, black , green and brown. More exotic specimen are completely black or have vibrant colors like orange, pink and red. 

They are completely reef safe, and though they will breed in an aquarium setting, they will not reach undesirable numbers. If you are lucky enough to find a Stomatella Snail in your aquarium, leave it in there and enjoy the fact that they are helping to keep undesirable algae at bay!

Some fish and shrimp will eat Stomatella Snails, they should not be kept with certain wrasses, particularly Six Line Wrasses & Four Line Wrasses, Peppermint Shrimp will also make short meals of them.

Tank Requirements

stomatella snail
stomatella snail
  • These snails are reef safe
  • Clean and stable water
  • Stable magnesium & calcium levels
  • Algae, if there is no algae in your tanks their diet can be supplemented with Nori (dried seaweed)
  • They will not tolerate a high nitrate level
  • Recommended stocking level is 1 – 5 snails per 20 gallons (90L) of water.


  • These are herbivores
  • Algae (diatoms, cyano, macro, and film, hair aglae)
  • Their diet can be supplemented with nori (dried seaweed)
  • Some aquarists have reported seeing these snails eating leftover flaked food


These snails take quite a long time to acclimate. They should be drip acclimatised slowly, for roughly double the amount of time you would do for a fish, about an hour and a half.

When placing it in the tank, it is best to place it on sturdy rock work rather than the sand as they prefer to be on the rock work.

Snails do not acclimate particularly well, so if after a couple of days you notice your snail is not moving you should place it somewhere that you can keep an eye on it, and if after another couple of days it still hasn’t moved, you should consider removing it from the tank.


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