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FAQs about Micro-Crustaceans Identification 3  

Related FAQs: Microcrustaceans/"Pods" 1, Microcrustaceans 2,
FAQs on: Micro-crustacean Amphipods, Copepods, other Small Shrimp-like ID 1, Small Crustacean ID 2, Small Crustacean ID 4, & Pod Behavior, Pod Compatibility, Pod Selection, Pod Systems, Pod Feeding, Pod Disease, Pod Reproduction, Amphipods, Copepods, Mysids, Brine Shrimp, Hermit Crabs, Shrimps, Cleaner Shrimps, Banded Coral Shrimp, Mantis Shrimp, Anemone Eating Shrimp, Refugiums, Crustaceans 1, Crustacean Identification Crustacean Selection, Crustacean Behavior, Crustacean Compatibility, Crustacean Systems, Crustacean Feeding, Crustacean Disease, Crustacean Reproduction,

Related Articles: Micro-Crustaceans, Amphipods, 'Pods: Delicious and Nutritious By Adelaide Rhodes, PhD, Copepods, Mysids, Hermit Crabs, Shrimps, Cleaner Shrimps, Banded Coral Shrimp, Mantis Shrimp, Anemone Eating Shrimp

Skunk cleaner shrimp pregnant... and sm. crust. ID f's      5/18/16
Hi all! I've read all your answers to others with my similar situation so I will be brief. In regards to feeding babies if I do get them, I read phytoplankton and baby brine are best.
<Mmm; yes... some species/sizes of the former. I'd (quickly) get out and read some reference works here>
If I have a plethora of brine shrimp breeding in all of my tanks especially my refugium,
<Really? Artemia? Not likely>
could I keep the babies in there and add phytoplankton?
<...? Not likely... they need to be reared in a purposeful culture system; lest they get sucked up, frappe'ed by pumping, water movement>
My brine shrimp look like little tadpoles swimming around everywhere.
<.... these aren't them>

If I have a huge self sustaining population, is it possible that there are enough need hatch ones to rear the baby cleaners if I supplement their diet with Phytofeast?
Thanks in advance! Tabitha
<Where to send you....? Please read here re searching /lit.:
And soon; you NEED to be culturing useful foodstuffs NOW. Bob Fenner>
My tiny swimming shrimp... Legless amphipods, Mysids, Copepods?

Sorry to send more questions but I can't help it. I LOVE learning things!
<Me too!>
If it is unlikely that I have Artemia populations in my tanks (240gal and 100gal), do you have any guess as to what they may be? Photos were taken through 20x microscope lens with my iPhone on just over half max zoom.
Actual size is 1/16" wide and just under 1/4" long. He's one of the biggest of them.
Thanks again Tabitha
<See here: http://www.wetwebmedia.com/crustidfaqs.htm
and the linked files in the series (in the tray at top). Bob Fenner>

re: Some help... Sm. crust., SW.... ID      9/20/15
Hello again chap, I haven't spoke to you in awhile hope things are good and okay.
I have some type of newly hatched baby shrimp of some kind I happen to see last night doing my rounds in my tank and I was using a flash light and happen to stand still long enough to watch about 100 tiny little animals doing different swimming patterns and then finally resting on the glass where my light was and I looked really hard cause they was hard to see and
they had clear body's with really big eyes on each side of the head, I knew they were newly hatched ,but I haven't added nothing as in live rock to my tank at all and its been up and running like 2months...
Is there any way I can find out at this age what I have growing in my tank???
Possible that mantis eggs some how hatch that was in there this long???
Here's pictures but they Ain't the best and I can't tell u now they are shrimp of somy type and was swimming in weird patterns... any help please and thank u mate... p.s I know what the little ting white dots are that's not what I am speaking of here though
<The photos don't help. No point sending us blurry white blobs! Most likely copepods, isopods, amphipods or similar... do read:
Mantis Shrimps have planktonic larvae that are very distinctive. Easily visible and identifiable with a microscope. So far as I know, they don't breed in aquaria... not those with traditional pumps, anyway. Cheers,
re: Some help...      9/20/15

Ouch!!! Let me see you take your phone and try to take pictures of little damn ass shrimp!!!
Really rude mate!!! But thanks for your professional help with nothing...
<Eh? Gave you three possibilities, with links so you can identify the creatures yourself. The photos you sent aren't in focus, so there's nothing I can do with them. I'm good, but not that good.>
good day
<It was. Cheers, Neale.>

Just a confirmation (I hope). Pod IDs        7/12/15
Hi folks,
As always thanks for all the help you give us. I had to "reset" my tank recently due to a overwhelming Aiptasia problem along with a bubble algae explosion. Went back with a DSB in both tank and sump. Slowly re-adding sterilized rock and lots of water changes. Doing well so far, but this morning I noticed some little white critters in bunches all over my glass.
I have ordered and released some amphipods to keep my mandarin fed, so pretty sure they came with them. As near as I can tell they are copepods.
<Indeed they are. The first likely a Harpacticoid, the second a Calanoid... not harmful; indeed beneficial>
I am inserting some microscope captures I made of them.
Have a great day,
<And you; Bob Fenner>

Critter ID question        4/8/15
yesterday I discovered hundreds of these little guys on some corals, All over an ORA blue Chalice, and some encrusting Psammarcora and Montipora.
The corals were in poorer health, Not sure if it was because of the critter or they were just being opportunistic. Tanks are bare bottom. Recent addition of a large amount of Chaeto to that holding tank (I own a store)
Sent the one blurry pic to Marc Levenson for ID, he was not sure. So I took the failing corals and gave them to a local vet and he put the critter under a scope. Said that its definitely a crustacean,
Looks like a flea,
Definitely has a mouth with biting parts.
I'm thinking this is something beyond a pod,
<MANY possibilities>
I've been doing this for about 15 years and never seen anything quite like it.
I attached the photo of the chalice I found them on, That chalice was fine up until yesterday when I found it looking like the photo.
Curious as to ID, and possible way to get rid of them!! (6 line wrasse maybe?)
<Yes! I'd try small-crustacean predatory fishes>
The system the tank is on is about 400 gallons. Not seeing anything in the other tanks with wrasses, not sure how long they've been around but I've never seen them before yesterday.
<As you know... such organisms do "pop up" seemingly from nowhere. Stocking a mix of.... Oh, let me see if we have summat archived re: Ah yes; read here: http://wetwebmedia.com/podcompfaqs.htm
Bob Fenner>
*Jennifer Kaufman*
*Aquarium Artisans *

I keep on getting small shrimps on the glass of my aquarium every couple of weeks, they are tiny and white and their numbers seem to increase rapidly then decrease again. Do you know what they could be, and whether they are dangerous to my aquarium inhabitants?
Also if they are dangerous how can I get rid of them? As they really take over the aquarium at times.
Thank You
Kevin L

What interesting organisms there are in our tanks! Turns out, there are several groups of such small crustaceans'¦ Shrimps, Amphipods, Copepods and so much more, that generally 'arrive' unannounced as hitchhikers on and in Live Rock'¦ The vast majority of such wee beasties are not only entirely harmless, but beneficial; helping to reduce noisome algal growth, keeping your substrate stirred (with its concomitant benefits), providing useful food-prey for your fishes and animal-consuming invertebrate livestock'¦and adding endless hours of entertainment and fodder for your further study of our hobby.
This being stated, there are some predaceous species of these micro-crustaceans that are deleterious. Particularly the Isopods'¦ these greyish rollie pollies, aka Pill bugs (yes, relatives to the harmless terrestrial ones) can be big trouble, attaching themselves to your fishes, even living in their mouths/buccal cavities, at times chewing away the equivalent of their 'tongue' and replacing same'¦ Yuck! These 'bugs' should be promptly removed with forceps/tweezers'¦
The vast majority of small hitchhiking crustaceans are beneficial however and should be more than tolerated'¦ they should be encouraged. In fact, one of the principal aims of having an attached live sump, otherwise known as a refugium, is to provide a predator-free area for the purposeful culture of such wildlife'¦ Allowing the errant individuals to either overflow or get pumped occasionally into the main/display tank where it will very likely be quickly consumed.
Unfortunately, resident populations of these helpful organisms that are not provided with a protected home (with rock, macro-algae, a DSB'¦) are often transient'¦ being consumed by fish livestock, or succeeded by other unfolding competitive life forms. Lucky is the person who happens upon the happy circumstances that foster these critters permanent status. Indeed, it is great to find a fellow marine aquarist who has such a population, and transplant part of their community to your new or established system.
Should you still not want these animals, being fastidious re maintenance, gravel vacuuming during water changes, feeding very sparingly'¦ will generally result in their numbers dwindling. BobF

Can you identify these little critters     12/9/13
Hey guys. Attached please find two pictures of the same little guy.
They appear in hundreds in my sump. The scoot around on their little legs quite rapidly. I _think_ they are harmless amphipods, but I just want to be sure.
Thanks guys for sharing your knowledge.
<As you say. Bob Fenner>

Identification of a "bug"    /RMF 7/27/13
Hi Crew,
First, thanks for being a great resource to aquarists. As  I can't seem find a positive ID for this guy on your site, I figured I'd ask. 
<Mmm, my guess/es are either an Ostracod or Cyprid (Barnacle) Cirripede larva>
Anyhow, I have been noticing a small bug-like specimen, maybe the size of a grain of sand crawling on some of my LPS and SPS coral. Usually I never see them in groups larger than 3 or 4 together. Still I was wondering if they are something to worry about.
<Mmm; probably not>
 I'm not sure which coral or rock they managed to hitchhike on but for sure it wasn't with the one Acropora I have as I noticed them prior to receiving this coral.
The picture I have attached is magnified about 100x.
Thanks for the help and thanks again for being such  a great resource.
<Ah welcome. Bob Fenner>

Re: Identification of a “bug”    /LynnZ    7/27/13
Hey Bob,
<Hey Lynn>
There was a query in my box this morning that I started working on, but was unable to finish at that time (we were taking off for a drive into the mountains).  Anyway, I just wrapped up the response and noticed that the query was gone.  I still have the querior's email address - do you want me to go ahead and send it on to him or send it along to you and let you post it?
 Thanks! Lynn
<Do send it along. I responded to it already... If you want the original msg., it's in the deleted folder. B>
Re: Identification of a “bug”

Here's a copy, just in case - thanks, Bob - Lynn
 Ahh! Forwarded to him. Thank you Lynn. BobF
Re: Identification of a “bug”

Thanks, Bob!
<Ah, thank you dear Lynn. B>
Identification of a “bug”:  Likely Ostracod – 7/27/13
Hi Crew,
<Hello Jim, Lynn here today.>
First, thanks for being a great resource to aquarists.
<On behalf of Bob and the rest of the crew, you’re most welcome, and thank you!>
As I can't seem find a positive ID for this guy on your site, I figured I'd ask.  Anyhow, I have been noticing a small bug-like specimen, maybe the size of a grain of sand crawling on some of my LPS and SPS coral.
<It appears to be a tiny crustacean called an Ostracod (aka a “seed shrimp”).>
Usually I never see them in groups larger than 3 or 4 together. Still I was wondering if they are something to worry about.
<I doubt it.  Benthic marine Ostracods are mostly comprised of harmless detritus/deposit-feeders, scavengers, herbivores (eating things like diatoms), and/or filter-feeders.  Some are reportedly commensals that attach themselves to other crustaceans, sponges, and echinoids/sea urchins and feed on whatever passes by.  Others apparently have specialized mouthparts for sucking the juices from plants, but I’m not sure if these species are found in marine habitats.  Before you breathe a complete sigh of relief, there are carnivorous/predatory Ostracods (some myodocopids) but these are either very large species, like those in the genus Giganticypris (which are planktonic, not benthic), or they’re small species that gather in large numbers and attack other crustaceans or even fish, en masse.  At any rate, the few individuals you have wandering about here and there are more than likely harmless and pose no active threat to corals and/or other
livestock.  Do search further on the ‘net for more information regarding these neat little creatures.  In the meantime, here’s a link that includes a key to the various subclasses: http://home.comcast.net/~fireflea2/OstracodeKeyindex.html 
A good photo here  (note the hair-like sensory organs called “sensilla”): http://www.flickr.com/photos/80125969@N00/2986624084
I'm not sure which coral or rock they managed to hitchhike on but for sure it wasn't with the one Acropora I have as I noticed them prior to receiving this coral.
 The picture I have attached is magnified about 100x.
<It’s terrific, thanks!>
Thanks for the help and thanks again for being such a great resource.
<You’re very welcome Jim, it’s always a pleasure to see the neat critters that pop up in people’s systems.>
<Take care, Lynn Z>
Re: Identification of a “bug”

Thanks to both of you, Bob and Lynn, for the info. I will research them and keep an eye on them.
<Ah, good. BobF>
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