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FAQs about Worms, Vermiform Animals of all Kinds 3

Related FAQs: Worms 1, Worms 2Worm Identification, & FAQs on: Worm Behavior, Worm Compatibility, Worm Selection, Worm Systems, Worm Feeding, Worm Disease, Worm Reproduction, & Polychaete Identification, Flatworms/Planaria, Fire/Bristle/Errantiate Polychaete Worms

Related Articles: Worms, Featherduster Worms

Worms of many kinds are inadvertently imported along with other livestock. Enjoy them. Monanchora unquifera in Jamaica... with some Ophiuroids et al.

Thank you from the Wriggle team!       6/23/16
Hi Bob
<Hey Harriet>
The Wriggle! exhibition finally opened last Saturday and it has been a great success! We are all really proud of how it looks, its interactivity and the fun that has been brought to the world of worms. It was designed for a family audience and the children are really loving it. None of this could have been achieved without the kind contributions from people such as yourself and we really are very grateful. Attached are just a few images so that you can get a bit of an idea of how it looks.
<Ahh! Very nice graphics/display>
A really big thank you for all of your help.
<Glad to do my small bit. BobF>
Best wishes
Harriet & team
Harriet Wood
Curator & Collection Manager Mollusca
Dept. Natural Sciences
National Museum of Wales
Cathays Park
Cardiff CF10 3NP
Wales, U.K.

dead worms in pieces in new tank   12/25/09
I'm in my 2nd week of cycling my 60 gallon tank, and yesterday we put in more live rock. there's about 30 pounds in there now and am planning to put more in next week. The LFS set up my tank with a Jaubert system. so today I wake up and there are about 6-7 balls of dark brown worms rolled up and not moving. then there's also 1 worm (about an inch) that is barely moving, squirming more like... but the weirdest part is there are other 'worms' that look like pieces of worms. some pieces are not even 1 millimetre long (range from 1millimetre to about half an inch). there are at least 20 tiny pieces like these and I can see white stuff that looks like it would be the inside of the worms. I think they are peanut worms but I'm just guessing from photos I've seen.
There's nothing in our tank as far as we know of, no fish etc. We didn't have this problem until we put the new live rocks in so I'm guessing it might have to do with that. Last week, we didn't even see these kind of worms in our tank.
<Oh, there's a bunch more life in/on your rocks to come!>
Is there something in the live rock that could have done this?
I've attached some photos you show you, you can't really see the really tiny pieces of worm from the photo but you can get a gist of it all. In the 2nd photo, you can sort of see the white bits I mentioned
Thanks for your help
<Not a worry. There are a few possibilities that could account for the worms coming out, being in pieces. These will decompose, otherwise be eaten, add to the readiness of your system. Observe, enjoy and learn. Bob Fenner> 


Re: dead worms in pieces in new tank 12/26/09
Hi Bob,
thanks for your reply! I've never had live rock in my tank before so after seeing all the bits of worms, I was a little concern about whether there could be anything living in the live rocks that may be harmful to any fish we eventually put in there once the cycling process is complete.
<Ahhh! Please read here: http://wetwebmedia.com/lridfaqs.htm
twixt all that is going on... and the linked files above, and where you lead yourself... B>
So I guess, leave the worms as they are and it should be fine?
Re: dead worms in pieces in new tank
Hi again,
just wanted to say thanks for your help!
<Welcome Kitty. B>

Help, tiny white worms... SW 8/31/09
I usually quarantine or freeze the shrimp feeders I catch after a check over for internal parasites and a freshwater rinse... well today I was in a hurry and just rinsed and dumped them in the main tank along with a few small fish that were by catch- thought the crabs would like them. Stupid stupid stupid. Now there are tiny, white worm-like creatures everywhere.
They appear to be about 1-3mm long with one end slightly darker than the other. Some are stuck to the glass and others are floating about in the current wriggling. I do not have any saltwater stored for a water change yet (just did one yesterday), but have been rinsing the pre-filter floss in hopes of mechanical removal. My fish is discolored, lethargic, and laying at the bottom and I'm praying he makes the night until I can purchase some sort of medication late tomorrow.
<Medication? I'd be moving the fishes elsewhere... if you have space>
I cannot tell what sort of family these creatures are from or if they have attached to my fish (or are on his gills or innards) which is why I am requesting advice for a lead as to what I should use/purchase to kill them.
<There are Vermifuges... they have their downsides... Read here:
I hope my careless mistake does not cost me the life of the fish and these worms are harmless but I cannot seem to get a resolved photo for an ID.
Tank specs:
55 US gallon grow out tank
Ammonia, nitrates, and nitrites are all zero
SG 1.025
Residents are a 4 inch panther grouper (he will be moved to an 8' by 4' once large enough-
<Chromileptis gets too big for this system>
provided he lives through my mistake) and four hermit crabs.
<Bob Fenner>

A hungry roundworm - 11/20/07 Hi Bob, Great website. Thought you might find this interesting. I have afoot-long green ribbonworm in my 55 gallon tank that hitchhiked in some live rock. I thought it was harmless, but it swallows snails and hermit crabs whole! <Yikes... too big> Most are regurgitated alive because of the protection from the shell, but the last snail shell came out empty (it might have been swallowed empty.) Wondered if you had ever heard of anything like this. Ross <Yes... lots of neat animals in the seas... Not so wonderful at times in our "glass boxes". Cheers, BobF>

How To Get Rid Of Hair Worms… Why Would You Want To? - 09/14/07 Hey guys, <Hi Josh, you've got one of the gals tonight.> I have done some looking on your website and it appears that what I have in my tank are hair worms. They are about 1-2 inches long, about as thick as hair, and white and kinda fuzzy toward the ends. I've read that they are completely harmless, so I'm not worried about them hurting anything, but they are multiplying like crazy. I started with just a couple that I believe came in on a frogspawn I bought. Now I have roughly 25-30 of them in a 9-gallon tank! <Lucky you!> There are a lot of them on one particular rock near my Zoas and they are constantly brushing them causing them to close up. <I wouldn't be too concerned. I doubt the Zoas are suffering.> Is there anything that eats these guys or anything I can do to get rid of them? <Oh, I would discourage you from doing this. These are quite beneficial to your system and have many predators, so you are lucky to have them. Predators include hermit crabs, cleaner shrimp and many nipping fish.> It's a little unattractive to have 25-30 white strands of hair blowing around all in your tank. <Perhaps a little relocation?> Thanks for everything, <Welcome! Mich> Josh

Feather Duster & Worm Questions Hello again, crew.<Hello, MikeB here.>  I have a feather duster/worm question for you.  I looked through everything I could find on the site and couldn't find any information on it, so please forgive me if I missed this in some previous answer. <Sure, no problem.>  We originally had 2 Hawaiian feather dusters and 1 small, dark purple feather duster.  The small feather duster (don't have a more accurate name) had what seemed like a calcareous tube that looked like it was made of substrate - not like the leathery tubes of the other two.  The Hawaiians seem to be doing just great, and we have a number of other dusters that have begun growing on live rock.  However, a couple of months ago, the small feather duster appeared to have died - the feather crown fell off, tube in several pieces, no visible worm.  We cleared out the old crown and empty pieces of tube that were easy to reach, leaving one small (maybe 3/4") piece of tube that was under a rock shelf that not as easy to get to.  There is now a lot of activity originating in the old piece of tube, which we hope means the original worm is still around.<If the worm gets stressed it will drop its head and eventually a new one will regrow.>  There are many grayish, thread-like projections coming from the tube (like 40-50)  that spread out to cover a pretty wide area of substrate and appear to be moving small substrate pieces back toward the tube.  Our concern is to make sure it's the original duster worm doing his or her thing, vs. another species that might not be such good news that might simply be opportunistically using the old tube section.<My hunch is that it is the old feather duster trying to reattach itself on the live rock or substrate.>  I didn't see anything on the site about these hair or thread projections.   Finally, on what I think is an unrelated topic (we have given up on being sure of anything), we have noticed that we have some pink and some white worms in that general "construction" area of the substrate.  We think they would be called bristle worms.<You are correct.>  We haven't seen them elsewhere, although maybe we just missed them.  Related? <No they are not related to feather dusters.>  Meaningful? <They are good for substrate circulation but can be a nuisance if they are in large proportions.> Get a life and quit looking at the tank? <Absolutely not, I live by looking at my tank.>  Thanks, as always.  This is absolutely the best resource on the web; wish we had known about it all along, but it saves us regularly now. Laura & Jim <Good Luck, MikeB>

- Worm ID - Hi, I am very new to the saltwater hobby.  I have a 90 gallon FO tank, has been up and running for about 2 months.  I have started to notice very small ( size of a hair) black worms in my sand and on my rock.  Any idea what they are and if they are bad. <I think they are small, black worms... probably not harmful.> Like I said they are the size of a hair and maybe 1/4" long and black?? <Sorry I don't have a more exact answer for you, but the worms are among the most diverse group of organisms on the planet. Hard for even the PhD's to be true experts, and I am neither.> Thanks,
<Cheers, J -- >

Worm Spawning 2/9/04 Good evening Anthony? <and to you Morgan :)> Hope your life is salty and wet. ;]   <Oh, so many wonder responses to that open door comment.> I wrote about my flame scallop a while back, I've had it for a year now and its still happy and growing.   <good to hear... any ideas why that you might share with us?> So I bought a big white one to keep it company.   <Ughhh... you know, they say that lightning never strikes the same place twice> hehehe  Its a good thing I'm an experienced reefer eh? lol <Ahh... or the other side of that coin is "even a blind squirrel finds a nut sometimes"> Well this evening I  turned the lights back on after about two hours to finish fragging an Acropora and clean the glass.  After an hour or so I noticed white cloudy stuff coming from the area of my Anacropora.  I lifted up the colony and found that my rock boring worm? was spawning.   <very cool> Pretty darn sure, it didn't look like rock dust and the worm went at it for a long time.  I always figured I had some sort of worm in the rock because it would leave tube-like stuff (like thin feather duster tubing) around the holes and underneath other rocks.  I tried to id it on the web but I couldn't find anything close to what it is.  So here I am... ;]   If you look at the close up picture you can see a hole with xenia close by, you can see 2 tentacles that are banded brown and white.  Well I hope you can see them...   <not clear in the <1% of the image that they occupy <G>. A closer/full-frame shot would help if possible> Anyway, this guy has 5 brown and white banded tentacles surrounding a mouth?, like a calcareous tube worm mouth.  I figure this is some type of Serpulid? worm, but I've never seen one with 5 tentacles.  Hope you enjoy the sexy pictures. ;] Sweet dreams! Morgan Mok <the event is really neat. And much appreciation for sharing the pics and report. I wish I could be of more help with the ID, but it would be nothing more than a guess at this point. Do send a better photo is possible and I'll give it the old college try :) Anthony>

Spaghetti worms - marine 1/14/04 I've looked and looked and looked and can't really seem to find the answer to this questions, so could you PLEASE HELP???  Are spaghetti worms something to worry about in a salt water aquarium tank?   <they are very helpful... detritivores. I'm not sure where exactly you were looking... but a simple keyword search on Google or another large search engine turns up hundreds of references to these desirable denizens of marine substrates> I've just discovered some coming out of the live rock.  Let me know if they need to be fished out or are actually a good critter to have in there.  THANKS!   Jen <they are as good as gold if you could breed and sell them. Keepers. Anthony>

Nuisance crab and worm Hello <Hi. Steve Allen here tonight> I have started a new 55 gallon reef tank. Its been up and running for just under a month. After adding my live rock I happened to notice a number of what I suspect are bristle worms. The problem is in one piece of live rock there was a very large worm. It's length was approximately 3 to 4 inches and that was the part sticking out of the rock. Since my attention has been drawn to this large piece of rock I have noticed that there is a good sized crab living within and under it. I haven't been able to identify it yet but when I shine a pen light into one of the holes in the rock I can see that its quit large. In any event I want both of these creatures gone. <A bristle worm of this size is not really a problem. Read through the Bristleworm FAQs before you commit to getting rid of it.> I have tried trapping the worm by wrapping brine shrimp in a weighted nylon stocking, but that has failed. <There are better ways. Check the FAQs.> My question is since this tank is still so new, can I remove the rock and try extracting these creatures? I have heard that I could run the rock under fresh water and the worms and crab will exit and I have heard that I could submerge the rock in a high salt content water and they will vacate. <Number 2 is the better way to go. SG >1.030 > What would your suggestions be? I have also attached the tank log for your inspection <nice log. Do you have Excel? A spreadsheet is a nice way to track/trend your parameters.> thank you for the help <Hope this helps.>

Planarians maybe you can help me, I need too kill planarians hope that is the correct name) once and for all I'll be most grateful for this information.    best regards. <Please read here: http://www.wetwebmedia.com/pestflatwrmanthony.htm and the linked (in blue, at top) files beyond. Bob Fenner>

- Worm Caused Tank Crash, News at 11 - Guys, I have asked you a few questions in the past.  Your answers have not only helped me but the LFS with whom I do a lot of business and have passed on your advice.    I am writing this email on behalf of the LFS.  Something very strange happened that caused a tank crash in a 125g reef.  He started noticing a small (pin head sized) white worms eating a plate coral.  Within 1 day, there were hundreds of these that ate the flesh and killed the plate, a nearby Fungia, a brain and numerous other corals.  There are skeletons left at this point (3 days later).  This tank is used to sell corals, so it has high turnover of stock.     I haven't seen a worm caused crash in any of your FAQs.  What could this be? <Probably not what it looks like - in my experience, most worms are harmless but still opportunistic meaning they won't pass up an easy meal. Typically they are lured out into the open by dead or dying organisms and arrive en masse to consume the necrotic flesh. I've often heard reports from folks who say, "Bristle worms have killed my coral." When in fact, the coral was already dying and the worms were just doing what they do. There are predatory worms, but they are typically larger and most often singular in occurrence in the aquarium... the folks at the LFS would have lost other corals before this.> Have you heard of this before? He would like to know, if possible, where these worms come from so he won't order corals that originate from that area for a while. <Impossible to say 'where' they came from.> This infestation occurred quickly and spread throughout the tank within a very short period of time. <Again, my thought here is that the death of the coral and the appearance of the worms is somewhat coincidental - likely the worms have always been there but perhaps this is the first Fungia that began to die before it was sold.> This is somewhat scary. <Perhaps for the easily scared - I personally really wouldn't worry about this too much.> Would peppermints/arrow crabs/6-line wrasse help? <Wouldn't hurt - would certainly keep such a population under control.> What other creatures would help? <I think just about any of the Pseudocheilinus wrasses would work... probably any of the small wrasses would work.> The water chemistry is perfect.  The tank isn't fed, so there isn't nutrient problem.   Thanks very much.   <Cheers, J -- >

Hitchhiker/Worm ID: Sipunculid... AKA Peanut Worm, rest easy 8/25/03 I found this worm(?) in my tank this morning.  Any ID help would be greatly appreciated.   It is a Sipunculid... AKA peanut worm... delightfully useful and harmless detritivores> Is this a good or bad thing? <do enjoy> I am attaching the picture. Rich <best regards, Anthony>

Identification of worm - 8/17/03 I found this worm-like creature crawling on my leg while I was doing dishes.  Can you please help me identify it? <hmmm... nope, but it does remind me of how humid FL is and how I dread the bugs there <G>> Thanks Michelle Robertson Florida <an underwater pic would be easier for the ID. to see the setae, if any, and the appendages. Best regards... wear thick stockings. Anthony>

Worm ID - 08/12/03 <Hi John, PF answering your message today> Hello there, Great site you have here.... and greetings from Finland..  One question, I find last weekend bright red thing in my tanks coral bottom, it was inside the coral sand and all around it the coral sand was black ( like  carbon), and in the other end of that worm it has a lot of  long thin tentacles. I leave the worm alone and it bury it self inside the coral sand only the tentacles are over the sand and are moving all over. the worm is about 2cm long and the tentacles much more.  So any ideas what can that be ?? <Go here: http://www.wetwebmedia.com/polychaetes.htm and about half way down the page is a picture of a spaghetti worm. They come in a number of colors including red, white, and orange. Is this what you saw? If so, it a beneficial scavenger, and will hopefully reproduce in your tank. Have a good one, PF> Thank you and Best Regards,

Hitch hiker ID Please? Folks, <Howdy> The attached picture is of a "creature" that I found in my new 75 gallon reef tank. <No file attached> The tank is cycling with live rock only at this time.  There are a few smallish crabs and snails and whatnot that came in on the live rock; no harm done.  However, I found this "thing" crawling around on the DSB yesterday.  It moves like an inchworm, attaching to surfaces with its mouth and pulling itself into a bell curve before attaching with its tail and so on.  The scary thing is that the oral opening looks A LOT like a lamprey.  Unlike lamprey, it has a suction cup like tail as well. <Ah ha! (imagine best Sherlock Holmes impression). Does sound like a leech> I've posted on many boards and everyone seems stumped.  I was wondering if you could help.  I do have SOME time as the tank is cycling.  However, I don't want to lose track of it, or "let it be" if it is harmful.   <I'd remove this animal> I'd sure be upset if I found it one day attached to and sucking the life out of my clowns or Dottyback!  Thank you in advance, David PS.  I've read the Reef Invert book from cover to cover and am on round two.  It's a great resource and is extremely entertaining in that "Fenner, Calfo, WWM" way. <Mmm, sometimes predictability is fine. Bob Fenner>

Re: Hitch hiker ID Please? Boy it's been a long week ;)  Sorry.  Picture is now attached. <D> <Much more definitely a leech. Again, I'd give it the heave-ho. All Hirudineans are parasitic... Bob Fenner>

Worm ID: Eurythoe Fireworms... Yikes! 7/8/03 Alrighty, here are a couple of pictures: <thanks for the follow-up. Your worm unfortunately is a Eurythoe Fireworm. Indeed predatory and even slight risk to you (painful setae/bristles) can be shed/shot into your skin. Do use the name provided to browse our website and the Web for more on the subject. We also chat about these critters versus the harmless bristleworms at length in our new book on Reef Invertebrates (P. 172): https://secure.wetwebmedia.com/order_form.jsp  for signed copies of the book  http://wetwebfotos.com/store/nma-ri.html  best regards! Anthony>

Another Worm Question for Ya - 7/7/03 Anthony or Bob, <Cheers, my friend> Hey there!  Hope all is well with all of you and yours.  First, I want to say your new invertebrate book is excellent.  When will the next book in the series be coming out?   <Gracias! And we're hoping to have the new book out within 12 months... less likely.> Been awhile since I've written.  No problems lately!  Ha-ha!  Tank is going extremely well.  Many incidental sponges and what appears to be a tunicate have taken hold and are growing very quickly (the tunicate organism is quite large and still expanding).  If it is a tunicate that would be surprising but in a good way.  Corals and invertebrates doing extremely well.  A Sarcophyton has put on about 9cm in the past 6 months.   <Outstanding> Well anyway...  The issue is a very large Polychaete, or what I believe is a Polychaete.  I've attached 9 pictures compressed in .zip format.   <Cannot read/open the zipped files... please resend simply as downsized jpegs my friend. Only a couple needed. Thanks kindly, Anthony>

Hair and Spaghetti worms 6/10/03 Hello, <Cheers> I was looking at my live rock last night and saw a Long white tentacle coming out of one of my pieces of live rock. It stretched out about 5 inches!!!! What in the world do you think this is? <One of many harmless if not beneficial worms. The multi-tentacled ones are commonly referred to as "Spaghetti worms"... the ones with a single pair of tentacles (you perhaps saw only one) are Hair worms (Spionids). All are quite good scavengers.> What ever it is in that rock, it must be big. I'm scared to pick it up and look in fear it will take my finger off at the elbow!!!! Any Ideas? <Hmmm... yes: offer no more than to the wrist.> Regards, Jason Mobile, Alabama
<Kindly, Anthony>

Small, transparent worms <Hi Meonne, PF here this AM> Please help me identify and provide suggestions on what I need to do about the small (inch or less), almost invisible, transparent worms in my 75 gallon saltwater tank.  My tank has been setup for 7.5 weeks now.  I also noticed some tiny white worms on the sides of my tank glass.  I think I found out by reading your website that they are harmless and I just need to stop feeding my fish for 3-4 days to help eliminate them.  Please advise.  Thanks, Meonne <Well Meonne, unless they are in plague proportions, I wouldn't worry about them. Many organisms come and go over the lifetime of a tank as conditions change to favor some over others. Currently, I have a number of small worms myself that have only recently appeared. If you really want to cut down on their numbers, you could stop feeding the fish, or maybe just feed them less so that there is not so much food available for them. About 99% of all the worms in our tanks our harmless, and the other 1% may not even be harmful to anything you have in your tank. If they grow to plague proportions, write back with more details about your tank (water parameters, inhabitants, etc.) and we can give you better advise. Have a nice day, PF>

ID this worm I found this little bugger crawling around the other day and I couldn't get a good shot of him in the tank so I pulled him out. Extended he is about 6 inches long. When he moves he actually pulls his body into himself then pushes it back out. What is this and is it good or bad? I know the PIC isn't real clear. I got a new camera and still haven't figured what settings are the ones to use. He has small black line encircling his entire body. At first it looked segmented but looking closer they are just markings. Help me. Oh yeah by the way you guys rock!!! <Thanks. Looks like a Peanut Worm (Sipunculid) to me. You can see a few of these on WWM or use your Net search tools with these terms for much more. Bob Fenner>

Tiny white worms? Hi.... <Hi Luke, Don here> my tank is about 4 weeks old. I've noticed today that suddenly a huge number of little tiny white 'lines' appeared on the sides of my tank. They were moving and quite fast actually. They seem everywhere and there's tons of them. About 1mm in length I would say. What are those? Are they bad for inverts or fish? <These are worms that appear as a part of the natural progression a new tank goes through. Not to worry. If they are on a viewing pane, you can scrape them off very easily.> Thank you,  Luke

Worm Picture (terrestrial Annelid) 5/2/03 a colleague in a next door office has found a rather large worm living under his garage in Timperley, Altrincham, Cheshire, UK <extraordinary... I'd say this specimen has been consuming wolf cookies and drinking gorilla milk <G>> he manage to get the attached photograph of it - note the ruler to gauge the size....when he approaches it, it seems to go very rigid and then disappears down its hole again very quickly. <I'm surprised that it does not stand and fight!> Could you help identify whether it is just a very large common earthworm ? Thanks Keith Purvis <alas, even with a good picture, my knowledge of terrestrial Annelid worms would likely fail you... its hard enough identifying the salty aquatic ones <G>. Perhaps you might stir up some data about such worms regionally  using key-phrase searches on the Internet using the words: Oligochaeta, Annelid, Terrestrial, and perhaps locale (UK/Cheshire)? Thanks kindly for sharing the photo. Remarkable :) Best regards, Anthony>

Worms in my reef tank >Now I know that you get asked so many questions about worms in a reef tank and I have gone over recently asked questions and answers and mine just don't seem to fit.  In my reef tank I am getting an over abundance of white, long stringy worms that live in tubular structures in my rock.   >>Do they seem to build their own structures? >They have now eaten my flame scallop, clown goby, and other small invertebrates.  I have heard of making a trap, but they don't ever fully come out of their holes.   >>Something doesn't jive, here.  If they *never* fully come out of their holes/tubes, then how would they be eating your other specimens?  It's not uncommon for some worms to eat dead or dying animals (of which the flame scallop would be a highly likely candidate), but not so for the tube worms I'm familiar with.  Also, any pictures you could send would be helpful in identification, along with sizes and so on.  Once we get some of that information an ID would be a bit easier, though I can't guarantee it. >You can sit and watch them.  They are long, single stringed, no crown or branches off the head or body and are carnivorous worms.  How do I start to single out a few?   >>Clearly, your husbandry of these worms is outstanding and they're proliferating.  Not just surviving, but thriving as it were. >They do not bother peppermint shrimp, but they don't eat them either.

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