Burrowing Sea Cucumbers, or sand sifting sea cucumbers, are most likely either Ocnus surinamensis or Phyllophorus occidentalis. Both are very popular for sand and mud sifters for reef tanks and refugiums. They spend all of their time under the sand burrowing through it, and about the only thing you’ll usually see are the dendritic feeding tentacles, which line their mouth. These tentacles dont seem to be able to sting but they somehow catch and trap sediment and detritus, which they ingest and eat, then periodically expel and start catching more stuff. They are one of the only cucumbers that actually live under the surface of the sand, and they do burrow through it, but not very fast and not very far.
Since they live under the sand, they aren’t much trouble to any other tank mates. As far as I’ve been told, they are reef safe and coral safe, and
nothing seems to eat them. Most customers buy them as sand sifters, and they are good at that.
Like some other sea cucumbers, they can release a toxin when stressed, but it takes a lot to stress them, and unless you have dozens in a smaller tank,
there arent enough toxins to cause a problem. When you acclimate them to their new tank, it would be a good idea to discard the acclimation water after youve introduced them to your
system so that any potential toxins released during shipping are not introduced into your system.
These are small cucumbers. They will get up to about 3 long when full grown, but can also shrink from 3 to 1.5 if disturbed. They will be about the size
of a pecan when you get them.
Michael (verified owner) –
I ordered one of these, Kara sent two.
They are definitely odd creatures but pretty in their own way.
One of mine is a rust color the other came in a tan/brown.
The rust color one has not moved but the other has already burrowed and released it’s frilly appendages. It is no longer tanish brown but a mottled black and white. Pretty nifty animals. Glad I ordered it!
Robin Stafford –
I’ve got three of these guys in my 185. They don’t take up much room and nothing seems to bother them. It may take a day or two before they find their spot, but once they do they’re out most of the time, just looking for an easy meal. The picture doesn’t really do them justice. Under my lights, their feeding tentacles are white and frilly. I love them. I’ve never seen them offered anywhere else – another reason I love KA. Thanks!
Phyllis Crubaugh –
I really expected a rather ugly creature to arrive, never having had one and only the picture to go by. They are really quite lovely. They came in balled up like a closed urchin and unfurled to surprise me. They went under the sand and right to work but left their tenticles out and happy. I will be getting more of these. Thank you.
Moses Taryanik –
Very cool little critters! I purchased 5 and still have them all. Very cool to look at when they have their feeding tentacles out. A++++!
Carol Anderson –
Awesome critters. It is neat to watch the tentacles waving out of the sand and if a fish swims by, they disappear.
Wayne Stuck –
This guy took off right into my sandbed when I placed him into the tank. Haven;t ssen to much of him but he’s moving the sandbed around.
Red Angel –
Ordered 1 got two thought they were supposed to be ugly but neat lokking in their own way