FAQs about Live Rock Hitchhiker/Creature
Related Articles: Live
Rock, Reef Systems, Refugiums,
Related FAQs: Live Rock, Answering
Some LR FAQs by James Fatherree, LR
Hitchhiker ID 1, LR Hitchhiker ID
2, LR Hitchhiker ID 3, LR Hitchhiker ID 4, LR Hitchhiker ID
5, LR ID
6, LR ID 7, LR ID 8, LR ID 9,
LR ID 10, LR
ID 11, LR ID 12, LR ID 13, LR ID
14, LR ID 15, LR ID 16, LR ID17,
LRID 18, LRID
19, LRID 20, LRID 21, LRID 22,
LRID 23, LRID
24, LRID 25, LRID 27, LRID 28, LRID 29,
LRID 30, LRID 31,
LRID 32, LRID 33,
LRID 34, LRID 35,
LRID 36, LRID 37,
Non-Vert IDs 1, Tubeworm ID, Polychaete Identification, Live Rock 1, LR 2,
LR 3, LR 4,
LR 5, Curing
Live Rock, Live Rock Selection,
Shipping/Moving, Placement, Lighting, Water Quality, Live Rock Studies in Fiji Collaboration
& Charts, Copper Use, Marine
Landscaping, Marine Biotope,
Sumps, Refugiums, Faux
Help ID This Liverock Hitchhiker 9/20/10
Hi WetWebMedia Crew
Thank you so much for your help previously - I have removed no
less than 10 crabs from my liverock and I think I have one more
Could you please help me id this creature on my Indonesian
Seems to have popped out of nowhere - my tank has just passed a
month of the cycling process. I think it's a button polyp
from the pics that I have seen but would really like confirmation
as I would hate if it was some sort of pest anemone and I just
let it proliferate.
<No pest, appears to be a Palythoa of some sort.>
thanks once again.
You're welcome from Michigan, USA. James (Salty Dog)>
regards from South Africa!
Strange white large lump on live rock
I'm new to salt water. I've got this 5cm roundish large
lump growing on live rock. It is a couple of days since this
photo, and now the white is almost completely solid white and
The pet store said it was die off and to scrub off the white.
<Is what I'd advise. Looks to be some sort of
I did that and it grew back overnight. I scrubbed it off again
the next day and noticed it wasn't rock underneath but
something squiggy, sponge like.
It seems to have a crusty outside and when I poked it a little
there was some red thick creamy like stuff that protruded from a
couple of spots.
Any idea what this is and how I should deal with it?
<Perhaps it's some sort of sponge underneath... Appears to
be so small as not to be a problem. Maybe leave alone and see
what it develops into. Bob Fenner, who wishes folks would follow
our guidelines for limiting file/image size. Yours are an order
of magnitude too large>
Mysterious Visitor - 8/9/10
White stuff growing on live rock. 9/3/10
There is sponge looking stuff growing on my live rock, when I
touch it, its very soft and crumbles. But is growing more and in
different spots. Please take a look.
<Is/are (Syconoid) sponges... see WWM re. Bob Fenner>
<Hello Debby, Lynn here this evening.>
I have a 55 gallon saltwater aquarium. It consists of live rock,
canister filter, good water quality, protein skimmer, and weekly water
changes of 7-10 gallons. I am using the high quality salt that the
Saltwater Aquarium store recommended.
There are 5 Chromis, 1 Maroon Clown, 2 Cleaner Shrimp, 1 6 Line
Hawaiian Wrasse, 1 Blue Damsel, and I am hoping the Watchman Goby is
there hiding, but I fear not as I haven't seen him in a week. There
are various small corals I have slowly added, as well as a leather
coral and 3 small mushroom corals. Everything seems to be thriving.
A week ago I noticed a deep, deep black "thing" on the rock.
I was in a hurry and decided I would examine it later. When I went
back, I didn't see it. Tonight, about an hour before the timer
would turn the lights out, I noticed three ink-black things. I tried to
explore your "FAQs" but I have no idea where to start.
<<Ahh, Lynn... we need to have "that" dichotomous key.
Re: re: mysterious visitor
>Let's do it! -Lynn<
<<Am putting on my (sigh) analog calendar... and will make time
to make incremental progress... I DO think/feel, okay, make that know
that we will have fun doing this. BobF>>
They don't appear to have a shell. They almost look like a small,
muscular slug. There are the smallest white specks that appear to be
towards the head of the things, and they do move, rather slowly, but
they move. Any suggestions?
<It could be a Scutus, a mostly herbivorous Limpet-like creature
that's often mistaken for a Seaslug. Most hitchhiking varieties
have whitish elongate shells that are most often obscured by the
snail's black soft tissue mantle. Typically, all you see of the
shell is a sliver of white along the middle of the back. Please see the
related FAQ's at the following link for photos and more
information: http://www.wetwebmedia.com/LimpetID2.htm . If what you see
there doesn't look like what you have, do what you can to get us a
photo so we can give it another try. There are plenty of other
I haven't seen any of the corals or fish looking harmed (besides
the missing goby), but they look a little suspicious....... please
<Let me/us know if what you have is not a Scutus.>
Thank you so much for your time and consideration.
<You're very welcome.>
<Take care, Lynn Z>
Re: Mysterious Visitor: Likely Scutus spp. --
Thank you very much, Lynn, for your response.
<You're very welcome.>
I believe you have identified my interesting little fellows. Your
picture looked very much like them, and although I will double check
tomorrow (if they should choose to come into sight), I am fairly
certain that is who they are.
<Sounds good. If it turns out to be something else, just snap a
photo or two and we'll have another go.>
Thank you very much. Having this resource is definitely a relief --
seeing unidentified creatures appear can be alarming.
<Yes, it certainly can. Thankfully, most of the creatures that
hitchhike into our tanks via live rock are either beneficial or at
least innocuous. It's a whole other story when something hitchhikes
in on a new coral!>
You are appreciated!
<Thank you so much, it was a pleasure!>
<Take care, Lynn Z>
Something Lilac. 8/8/10
<Fraser, sorry for the delayed resp. Have been out>
Long time viewer, first time writer.
<You are a stranger here but once>
Could you have a look at the attached photographs and let me know
if you can identify what the spiky purple stuff is, and if so,
how to get rid of it.
<Mmm, might be a sponge of some sort... my second guess is an
I have an 80 gallon marine tank with lots of rock, lots of flow,
very good water quality and a good skimmer. This stuff I cannot
shake though. I remove it weekly by the handful.
<I would continue to remove this material manually, as well as
seek out a biological predator... I'd take some of this
material to your local fish store and ask them to feed it to a
mix of fishes... To determine palatability. Do you have room for
a Rabbitfish species? Please read here: http://wetwebmedia.com/rbtfshselfaqs.htm
and the linked files above. You might greatly reduce
proliferation through improved nutrient limitation or export...
Read here: http://wetwebmedia.com/algnutrcontrolfaqs.htm
Good or Bad Hitchhiker? Usually Okay: Pseudocorynactis
spp. -- 8/3/10
<Hello Brenda, Lynn here today.>
I have sent 2 images of a "hitch hiker" that I cannot
A couple of these have appeared on live rock and I am praying
they are not some sort of bad anemone.
<No worries, they're definitely not anemones. What you
have is actually a type of Corallimorph (mushrooms, Ricordeas,
etc.) in the genus Pseudocorynactis, possibly Pseudocorynactis
caribbeorum, aka the Orange Ball Corallimorph. They're
commonly found in rock crevices and overhangs, and are mostly
nocturnal, opening at night to catch passing pods and
zooplankton. As for size, they can reportedly get fairly large,
but the norm in aquaria seems to be ~5cm/2 inches or less. Also
of note is that while these are carnivorous, since most are
nocturnal, the risk to fishes is slight. Even with
species/individuals that stay open during the day, fishes tend to
steer clear, just as they would an anemone.>
I have already killed an Aiptasia recently (it killed 4 Fungia
before I found it),
..but this does not look anything like the Aiptasia did,
<Nope, although these do share certain physical similarities
with Aiptasia, they're entirely different animals.>
This critter is translucent with iridescent colours, long
tentacles with a colored pom-pom at the end, about 1.5" in
diameter, and has a central mouth. It has always been in this
position in the tank and has not moved. I have looked everywhere
to find an image that looks anything like this and have not been
able to find any information.
<There are some excellent photos at this link:
We also have more information/photos at WWM. Just Google
Can you tell me what this might be, if it is something that can
harm corals or fish,
<The potential is there, yes, but in most cases, they're
..and if I should get rid of it?
<I would leave it/them until or unless you experience a
problem; for example, one encroaches on a coral, or the
population explodes. If you should find one uncomfortably close
to a coral, try eliminating it just as you would Aiptasia. As for
overpopulation, that's not something that occurs all that
often but under the right circumstances, it's possible so
avoid over-feeding. All in all, these are beautiful little
additions to systems that are for the most part
<You're very welcome.>
<Take care, Lynn Z>
Hope I am not to much of a bother!
I have recently converted my 90 gal tank to saltwater .... just
added fish this week it has been so exciting but to my question
... btw ur
<Oh please, no text type messaging, requires editing on our
forum has helped so much ..... I have this little guy growing out
of the live rock and I just want to make sure he is safe for the
others I have another thing very much like him on another piece
of rock but could not get a good pic . any help would be great
<What you have appears to be the dreaded Aiptasia Anemone. Can
multiply quickly and should be taken out of service. Read
James (Salty Dog)>