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FAQs about Marine Worms, Vermiform Animals Identification 18

Related FAQs: Worm IDs 1, Worm IDs 2, Worm IDs 3, Worm IDs 4, Worm IDs 5, Worm IDs 6, Worm IDs 7, Worm IDs 8, Worm IDs 9, Worm IDs 10, Worm ID 11, Worm ID 12, Worm ID 13, Worm ID 14, Worm ID 15, Worm ID 16, Worm ID 17, Worm ID 19, Worm ID 20, Worm ID 21, Worm ID 22, Worm ID 23, See Also: Flatworm ID 1 +, Nemertean, Proboscis, Ribbon Worm ID 1, Nematode, Roundworm ID 1, Nematomorpha, Horsehair Worm ID 1, Acanthocephalans, Thorny-headed Worm ID 1, Tubeworm/Featherduster ID 1 +, Bristle Worm ID 1 +, Hirudineans, Leech ID 1, Sipunculids, Peanut Worm ID 1, Echiuran Worm ID 1, Invertebrate Identification, Worms 1, Worms 2, Worms 3, Flatworms/Planaria, Fire/Bristleworms, FAQs on: Worm Behavior, Worm Compatibility, Worm Selection, Worm Systems, Worm Feeding, Worm Disease, Worm Reproduction,

Related Articles: Worms, Featherduster Worms,

Worm & Crab ID      8/18/13
I have spent hours on your site and Google.com trying to ID these creatures.  The worm(s) are dark then a small white section then a more greyish color.  Very tiny worm like creatures.  Those are Nerite eggs on the glass and they are about the size of one or two eggs. 
 <Looks to be some sort of flatworm; "Planaria" sort... not likely a worry>
The two crabs are two separate creatures I find at night roaming my tank. 
I think they are both the same species, but not absolutely sure.  I have found the molt from crab, but it was a bit bigger than either of these creatures.
I'm not sure if I have anything to worry about.
<General opportunistic omnivores; judging from their claws... are consuming some life in your system; more as time goes by... I'd be reading re Decapod compatibility on WWM>
 Our tank has not been at its best due to our special needs two year old. 
She is doing much better now giving us much more time for our water critters. 
 Thanks a Ton,
<Welcome. Bob Fenner> 

full size pic.

very tiny (0.5-1 mm long) white worms in saltwater tank... Food, under-filtration       04/14/13
Hello.  I'd like to say thanks ahead of time, and apologize if this question is already posted.  I couldn't find my specific problem.  I've spent a lot of time trying to identify these tiny worms and how to get rid of them, but nothing I come across seems to match.  I have a 36 gallon saltwater tank that has been running for almost 4 months.  There are hundreds of tiny tiny white worms on my glass and I'm sure on everything else, but its hard to tell because they are so small.  They are about 0.5 -1 mm in length, and far thinner in width.  They barely move around.  They are not curled or spiraled, and don't appear to be flat.  I've attached a picture that I took through a 10x magnifying glass.  The closest match I could find was possibly Planaria, but most people describe them as larger than these guys.
 <There are many possible species, even families that these could be... almost all innocuous... Of no harm to what people keep>
I am sure the worm population exploded because of overfeeding my fish. 
There are 2 clown fish, and a few small snails and crabs.  All my water parameters check out fine, temp is around 76, sg at 0.022.
<Mmm, missing the 1 in front. Your water is assuredly more dense than distilled>
 I started with an Aqua Clear 50 filter, but was plagued with cloudy water for about 2 months.  I decided to add a Bio-wheel 150 because I thought the Aqua Clear wasn't moving the water around enough.  I still had cloudy/murky water.
<I'd run both>
  I could see swirls of hundreds of tiny particles floating around.  After a month of this, I caved in and tried Kent marine clarifier. 
<Not a fan of such products>
After 2 doses over 2 days, it didn't help the cloudy water, it dropped my pH, and caused one of my clowns to have what I can only describe as seizures.  I have been diligent about weekly water changes (10-20%) and sand vacuums from the start.  Finally, about 2 weeks ago, my water cleared and the pH is back at 8.2.  When the water cleared was when I could really see the hundreds of tiny white "particles" stuck to the glass.  I did notice it before, but it was in small amounts, and I always would scrape it off.   The particles would just come back, and now in greater numbers.  It wasn't until about 3 days ago, when I took out a magnifying glass, that I realized the particles are worms.  I immediately reduced feeding, did a big scrape of the glass, rinsed my filters, added 50 micron felt to the filters, and did a big time siphon of the sand.  Sure enough, the little buggers are quickly repopulating on the glass.  Do you know what they are, and have any suggestions on what to do to get rid of them?
<As you state, some "type" of worm. As I've stated, not dangerous, though unsightly... As you mention, they are mainly "due" to your overfeeding... and under-filtration.
These worms will "go" with improved water quality, and time just going by... I would NOT treat the system to eradicate them... as their deaths might well present a toxic soup...>
 Also, and this may sound silly and paranoid, should I be worried about any human infection of these things?
<Not likely at all; no>
 The fish seem fine.  I always wash my hands after cleaning the tank, but these guys are so small, it does have me worried.  Thanks for your time.  I appreciate your help!
<Not to worry... Please search WWM w/ the string "Marine Worm Identification" and take some time perusing what we have there. Also consider reviewing our sections on marine filtration. All will be well here in time I assure you.
Bob Fenner>

Re: very tiny (0.5-1 mm long) white worms in saltwater tank    4/14/13
Thanks for the fast reply!  I am running both filters, and sorry about the typo, I did mean 1.022.  I'll just keep doing what I'm doing, and watch it with the food.  Thanks again!
<Certainly welcome. Cheers, BobF>

Re: Help Needed!!
Any idea what are these 2 things???  2/4/13
The green very long one , has it's bottom at the left of the screen , so as soon as you put a flashlight on it it shrinks in the hole at the left side.
It only gets out at late night after all the lights are gone and it goes back in the hole just before the lights light up early in the morning.
<... Likely an Echiuran. See here: http://www.wetwebmedia.com/echwrmidfaqs.htm
Also after these 2 creatures an Euphyllia is damaged and maybe a  Sarcophyton.
Best regards

Re: Help Needed!!  2/5/13
You are great !!! But you already know that !! :):):)
And the other creature??? You believe it is the same??
<The "stringy thing" of the same colour? Yes if so. BobF>
Re: Help Needed!!  2/5/13

Yup that was the one I was talking about.
Thank you again!!
<Ah, cheers!>

odd worms       12/12/12
Hello WetWeb crew,    A few days ago I noticed some odd creatures on my glass.  I have 30 gallon salt water tank that's been established for almost a year now.  They are about 1-3 mm long and sort of a brown red color
They look like small worms with bodies about a third as wide as they are long.  I thought they were stationary but upon further examination I noticed a few of them moving around.  They have a white tip were there head would be and their tails sort of form a "U" shape with the sides reaching out further then the middle.  What are these things?  And should I concerned about them?                 Thank you,                   Erik
<Likely some species of Polychaete, and not likely worrisome. With time going by, succession, predation by some other species, group, they'll likely pass. Bob Fenner>

Clear tube worm identification    11/17/12
I like your website and I hope you can help me out.   I was lifting a few pieces of live rock to see if my red banded Longfin Basslet was still alive (yes i found him nice and healthy).  However, I came across this clear tubed animal.  He has small tentacles for his mouth are and stretches around 2 inches.  He has a digestive tract that you can see.  I removed him and put him in a holding pen in my sump.  The picture enclosed is the best picture I can send you. Please let me know if you can identify this mysterious creature (I hope he is safe to put back in my dt)
<Mmm, this appears to be not a worm, but a sea cucumber... Not problematical... I'd put it back in your tank and enjoy it. Bob Fenner>

Powder Blue Tang, parasitic worm?    9/28/12
Good evening, I purchased a Powder Blue Tang, a Desjardini Tang and two Fairy Wrasse's through Liveaquaria.com a little over two weeks ago. They all went into a 29 gallon bare bottom quarantine tank with a few pieces of live rock out of my sump to help with water quality. I did twice daily water changes to maintain the water quality for the first 10 days when it finally leveled out. All of the fish are doing great, eating frozen Mysis in the morning followed with seaweed blend on a lettuce clip. Even the wrasses seem to enjoy eating the seaweed which surprised me. Anyways, all fish looked quite healthy when they arrived. I did not do a freshwater dip as I now see you recommend. The third day I saw what appeared to be a thread hanging on the eye of the Powder Blue Tang. I watched it closely for another day and it appeared to stay the same. Assuming it was a parasite I dosed the tank with PraziPro per instructions. Within 3 hours the
"thread" had detached and was on the bottom of the tank. I used a transfer pipette to suck it up and placed it under a microscope, please see attached photo.
<I see this/it>
I'm assuming some sort of a fluke.
<Mmm, a worm of some sort... but too spiny to be a Trematode in my experience>
I have not seen another one on any of the fish, nor have I seen any other signs of disease. I'm keeping the tank at 80 degrees and specific gravity of 1.020. My question is, I was doing such large water changes twice daily to keep the water quality up so I would replace the PraziPro with the appropriate amount but I only did this for four days. The instructions say to dose with a single treatment lasting for 5-7 days. Do I need to do another treatment or should I just continue to watch.
<I'd do the latter>
I plan on leaving them in quarantine for at least 4 to 5 weeks total as I know the Powder Blue's are known as ich magnets. Honestly, now that I've got them I'm completely paranoid that I will introduce crypto to my main tank, it's a 180 gallon reef and I've been down that road before several years ago. I left it fallow for 6 weeks and haven't had a problem since.
Would I be better off with a little longer quarantine?
<A trade off at about six weeks... little benefit vs. stress past that period of time>
I've read that the powder blues don't always do well so that is somewhat of a concern, however, this is one of the healthiest groups of fish that I've purchased in several years. Thanks for your time.
<Am going to "shop around" your pic... See what others think. To me this looks like a juvenile Errantiate Polychaete... Bob Fenner>

<Sabrina looked and she concurs that this appears to be a small Bristleworm... I think it/this "just happened" to be on the Tang... that it originated from the bit of live rock you'd placed in the tank. Not parasitic. BobF>

ID help with saltwater reef tank. - 5/7/2012
wwm: Hello James
Can you please ID this small creature which I found floating in my tank? I have posted on numerous saltwater forums, but have yet to get a decisive answer. I counted about 20 of them on the day of the recording. My current inhabitants (coral wise) are leathers, xenia, hammer, ricordea, candy cane, yellow polyps, and green/brown palys. Thank you very much for your time and dedication! http://www.youtube.com/watch?v=gScPDooDlyk 
wwm: Spintheridae worm. Feeds on sponges and possibly hydrozoans. A not so common hitch-hiker but not one to be overly concerned with. Numbers will decline as it's food source dwindles.
James Lee Galecio
wwm: Jordan

Hitchhiker ID/Worm ID 2/29/12
<Hello Paul>
I got a piece of live rock with lots of tiny holes all over it and the next day I saw some little arms coming from one of the holes.
At first I thought it may have been a tiny brittle star, but then two of the arms seemed to stretch much further then the others (and much too far for that size of brittle star).  Then I thought maybe some sort of worm.  It is a brownish color, but sometimes would look a little purple (maybe from the actinic blue light).  The longest I saw the "arms" stretch is about 3 inches.  The arms are also almost hair thin, maybe half of a millimeter.  Then there were two to three other arms that stayed close to the hole this creature was hiding in.  The most interesting thing about this little guy is the two longest arms
kept curling up into a spiral, almost making a cone shape from the spiral.  I would love to know what this neat creature is, and I've been searching the web and on WWM for a couple of days now, and nothing seems to quite fit the description.
<Very likely a Terebellid, a Spaghetti Worm.  Go here, scroll down to last picture.
James (Salty Dog)>
Re Hitchhiker ID/Worm ID 2/29/12

Thanks very much,
<You're welcome Paul.>
I have a clear spaghetti worm too on some other live rock!  The diversity of the ocean is amazing!
<Definitely so, very interesting for sure.  James (Salty Dog)>

Strange Inverts and writing 2/20/12
Dear WWM,
I have noticed some strange things in my reef tank. The first is most likely a type of round worm.
<What is this ID based on?>
It very much like a strand of fine hair that is moving around in the sand bed. Problem or not?
<Not likely>
I know that most round worms are parasitic,
<... not>
but I have no idea how I would even remove these from the system. Second, a type of tube worm. The tube is white in color and I suspect made of Calcium Carbonate. These are growing everywhere including the glass and seem to be reproducing by at least 25% per day. I don't think these are bad but I would like to know what they most likely are.
<... see WWM re>
I know pictures would help, but I do not have a camera that would focus on something that small. Third, these small things that remind me of capillaries. They are bright red and grow on the glass just above the sand substrate. The are tiny and have filaments that seemed to stick out from the tips. I also have noticed a barnacle on my Torch Coral. It has been there for well over two months now and seems to be growing like the coral.
When should it die? I only ask because I saw some people on the site had sent in similar emails and they were trying to I.D. the animal. Anyway, another thing I would like to know. I was looking on the site and saw that filters can be converted into refugiums. I would like to add a Mandarin Dragonet to the tank which is 55 gal. So I know I would need one.
<Would help>
I know I have a good supply of Amphipods and Copepods but I believe more are needed.
What would be best? Thanks for your time. Have a wonderful Monday. Or Tuesday depending on when you read this.
<... exactly why are you writing? B>

"Worm" in the shrimp/snail tank 1/28/12
Hi everyone,
Can you help me identify this "worm" in the picture? They appeared today.
I am wondering if they are harmful to the shrimp, snails, or me. This is about the best picture I can get. Should I clean out the tank and try to get rid of them?
<Mmm, how large is this one, others?>
I do a 10% water change every Saturday. I add conditioner to the new water and a little bit of Iodide for the shrimp. I feed Kent's Microvert, phytoplankton for the shrimp. Veggie rounds, shrimp pellets for the snails.
They also eat the algae that is on the side of the tank. The tank is in the sunshine so the baby snails will have algae to eat. Please advise.
Thank you
<Please read here: http://www.wetwebmedia.com/polychaewmcompfaq2.htm
Need to know size... not likely a problem. Bob Fenner>

full-size crop optimized

Re: Worm ID, in the shrimp/snail tank 1/31/12
They are the width of a hair and less than an inch long. They are all white and they move like an inch worm.
<Hmm, likely some sort of worm, but there are phyla that fit your description, image. Not likely harmful, deleterious... and will "go" of their own accord some day... mysteriously. BobF>

Reef worm ID 1/23/12
Hey crew of WWM, I'm not entirely sure how to properly go about critter identifications.
<Some day Lynn and I will get around to useful di, tri-chotomous keys>
Anyways I had this worm living in my Goniopora Sp symbiotically I'm assuming for well over 2 years. My Goniopora recently died a week back and the worm started to migrate eventually ending where i took this photo of it. Usually I never get to see it or be able to take a picture. I just want to know if it is reef safe primarily to stony corals.
<I'd keep it... does look bilaterally symmetrical... need to see, observe a good pic of the head itself... Doesn't appear to bear parapodia on the segments. In fact, this looks more like a very thin species of sea cucumber (Holothuroid) to me than a worm. Cheers, Bob Fenner>

Trails in my live sand, Worms... -- 12/23/11
We have 30gallon tank. Live rock and sand. A few damsels
<Mmm, what/which species? Not likely enough room here for "a few">
and a scooter Benny. We have some wormlike trails. Similar to what you would see left behind by an earthworm. We notice them more in the morning.
We have never seen a worm of any sort. Do you have any ideas?
<All sorts. There are literally thousands of species these might be... brought in w/ your LR and LS... Not likely harmful. Read here: http://www.wetwebmedia.com/worms.htm
and the linked files above. Bob Fenner>

Strange worms on glass -- 12/19/11
Good afternoon. Thank you for having this great site. I'm hoping that you can help me.
This morning I noticed about 100 of these strange yellow worms crawling all over the glass in my saltwater fish only tank. Should I be worried. What do you think can be. Thank you.
<Mmm, appear to be some sort of flatworm, "Planaria"... not really a worry, and will very likely disappear on their own in time (due to predation, lack of food...). Bob Fenner>

Worm id 12/8/11
Hi guys,
My brother bought a green, round worm with feathers around its mouth.
After about an hour searching around the web and checking your site, I decided to write and ask for an id and to ask what its functions are.
<Functions? In terms of what? This is not a worm, but an echinoderm... A species of Sea Cucumber>
Finally, will it wipe his coral and livestock out?
<Could cause trouble if died and dissolved w/o detection. See WWM re Cukes.
Bob Fenner>

And a flame "scallop", oh joy

What Is This Wonderful Creature?/Spaghetti Worm ID 11/27/11
Hi kind experts.
<Hello Tim>
I'm curing a batch of live rock, and I am overwhelmed with the diversity of life appearing. I'm slowly going through books and web sites to identify whatever I can, but this one has me stumped. I have several holes in live rock from which numerous tentacles sweep out. These smooth tentacles are at most a millimeter in diameter, probably less, and as long as eight inches or more! They are alternating bands of brown and blue. They can completely retract into their hole and vanish, but usually they are sweeping around the tank. Somehow this creature (I think it's one being as opposed to a bunch of worms, but of course I can't know for sure) builds a little white tube like structure over its hole, about 3 mm in diameter and 5 or so mm long. The tentacles come out the end of this tube. Once, a clumsy snail completely knocked the tube off of the rock, revealing the bare hole in the rock. The next morning the tube was completely rebuilt.
Any idea what this is?
<Sure sounds like a Spaghetti Worm to me. Spaghetti worms build elaborate tubes for themselves, either in the substrate or in small holes/cracks in the rocks.
The worm secretes its own cement from glands on its belly, then lines its tube home with coarse sand and small shell fragments. They are harmless and can be beneficial in cleaning up detritus and uneaten food bits. >
<You're welcome. James (Salty Dog)>

Re What Is This Wonderful Creature?/Spaghetti Worm ID//// Eunicid. RMF 11/28/11
James - Thank you!
<You're welcome, Tim.>
I had run across spaghetti worms in my search, but the first few pics I looked at did not look like what I had. But after you ID'd it, I did a more detailed search and found a few that look exactly what I have. There is a huge variety in appearance.
<Definitely so. There are many species of Spaghetti worms which are included in the 8,000+ known species of marine worms.>
<You're welcome. James (Salty Dog)>

Identification of Marine Organism 11/22/11
I am in need of help in identifying the organism shown in the attachment of this email. Also included is a map of where it was found (off the coast of Massachusetts). From what I can tell it is some type of sea worm, possibly a proboscis worm (Nemetera). Any information that would help in the Identification of this organism would be much appreciated!
<Does appear to be a Nemertean or Peanut Worm of some sort/species. You'd do well to send this specimen to a specialist at an east coast university in the field of worm taxonomy. Bob Fenner>

Some type of worm????? 7/11/11
Hey Guys,
<Howsit Jorge, Como que va?>
These are the best photos I could get of this guy that I found slowly (very, very sloooowly) slithering along my sump glass.
He has some pretty cool colors (red/brown and green) and some thin tentacles on one end. Whatever it is, it is not very coordinated and it has a very hard time moving.
Any ideas?
<Mmm, yes... looks to be a specimen of the family Terebellidae... an Errantiate Polychaete... See the Net, WWM re>
If by any chance I discovered a new species let me know so I can name it "WetWeb" ;)
<Oooh, or Bobsbierasomething>
<Welcome, por nada, Bob Fenner>
PS - He is out of the tank so no hurry at all in getting back....other than to kill my curiosity.

Re: Some type of worm????? 7/12/11
Wow...that was fast!
Thanks Bob!
PS - reef safe?
<Welcome and yes. BobF>

Worm ID 6/29/2011
Hi guys.
<Hello Leon>
I love your advice and willingness to help out people with questions. Your honest answers are amazing.
<Thank you, much appreciated.>
When I was doing some aquarium maintenance I found this (see picture) it appears to be a worm or larvae can you help me identify it? It is about 2 inches long.
<Appears to be a Sipunculid, a Peanut Worm. In the future, please do not send large photo files, resize to a couple of hundred kilobytes.>
<You're welcome. James (Salty Dog)>

Mystery worm ID 6/11/11
Hello WWM crew!
My name is Justin and I work at a local pet store. I'm currently attempting to become our aquatics specialist.
So to start off we usually have people come in with pictures or mysterious creatures from their RT that are found, so we can Id them. Today however, a young lady brought in a worm that I haven't seen in any book that we carry.
Its about 6 inches long when fully stretched out and has very fine feather duster-like tip.
<? Need a close up photo of this>
Its almost zebra striped with black and white sections. The odd part is that it retracts it's tip into itself like if you had pulled a pair of jeans inside out.
I did see a submission that sounded close to what I have presented you with, and you couldn't come up with an answer. The reason why I have resubmitted you with this question is because I have a picture and was hoping that it would be enough to help you with the answer.
Justin R.
Mystery worm ID pic
<I suspect this may be a member of the Echiura, though I see no example image via Google. Bob Fenner>

Re worm id... a vote for a peanut, nee Echiuran 6/13/2011
Hi Bob & crew,
I saw this image today on WWM and think that it could be a peanut worm - the description of the feeding apparatus and the striped introvert would suggest as much.
<Is also one of "next" guesses. Thanks, BobF>

Worm ID.
Hey crew,
I saw what I thought at first was some type of macro algae, but soon realized it is a worm of some sort. It looks like a piece of green, segmented algae (somewhat thick...maintains its rigidness under high flow)
with what looks like a pale orange balloon shape at the end sticking out of the rock. It sort of looks like tiny orange balloon attached to a thick green string.
Any ideas?
<Not from this description alone, no. The segmentation points to the Polychaeta, but... there are MANY possibilities. Need good well-resolved images of the head, processes in particular>
I may be able to get a photo, but I'll have to figure out the macro on my Canon first.
Loving what you do,
<Hopefully you'll one day be doing it with us. Bob Fenner>

Black and white banded worm ID? 4/24/11
Hey crew,
I've recently noticed another hitch hiker on the free piece of live rock I received. It appears to be 2-3 centimeters or so, no legs, and has 2 body segments per alternating black and white band (each colored band is approximately square shaped, maybe slightly more elongated). It is somewhat flattened, somewhat shaped by a bristle-worm with no head or legs. There are no visible eyes or antennae, and both ends are visibly the same, slightly tapering off.
<Good description>
I'm just curious as to what they are more than anything. What I saw in the archives were white worms with skinny black bands, but nothing exactly like mine.
If you can't ID it with that information, I will likely be able to get a high resolution picture as they increase in size.
Best regards,
<How about here: http://wetwebmedia.com/pnutwrmidfaqs.htm
or one of the worm ID FAQs files above? Bob Fenner>

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