Please visit our Sponsors
FAQs about Live Rock Hitchhiker/Creature Identification 26

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, LRID 38, & 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 Rock,

Help ID This Liverock Hitchhiker 9/20/10
Hi WetWebMedia Crew
<Hello Sujan>
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 to go.
Could you please help me id this creature on my Indonesian liverock?
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 9/6/2010
<Hello Penny>
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 membranish.
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 decomposition product>
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>

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>

Mysterious Visitor - 8/9/10
Good evening,
<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. B>>
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 possibilities!>
I haven't seen any of the corals or fish looking harmed (besides the missing goby), but they look a little suspicious....... please advise.
<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. -- 8/9/10
<Hello Debby!>
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
Hi Guys.
<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 algae...>
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.
Any ideas?
Fraser Levey
<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
Bob Fenner>

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 identify.
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, however?
<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: http://www.actiniaria.com/pseudocorynactis_caribbeorum.php
We also have more information/photos at WWM. Just Google 'Pseudocorynactis' here: http://www.wetwebmedia.com/Googlesearch.htm >
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 innocuous.>
..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 inoffensive.>
Much appreciated,
<You're very welcome.>
<Take care, Lynn Z>

Aiptasia 8/2/10
<Hey Fhrankey>
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 part.>
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 here.
James (Salty Dog)>

Become a Sponsor Features:
Daily FAQs FW Daily FAQs SW Pix of the Day FW Pix of the Day New On WWM
Helpful Links Hobbyist Forum Calendars Admin Index Cover Images
Featured Sponsors: