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FAQs about Green Macro-Algae Identification 7

Related Articles: Embracing Biodiversity, Green Algae By Mark E. Evans, Green AlgaeAvoiding Algae Problems in Marine System, Algae Control, Marine Maintenance, Nutrient Control and Export, Marine Scavengers, Snails, Hermit Crabs, Mithrax/Emerald Green Crabs, Sea Urchins, Blennies, Algae Filters, Ctenochaetus/Bristle Mouth Tangs, Zebrasoma/Sailfin Tangs, Skimmers, Skimmer Selection, Marine Algae, Coralline Algae, Green Algae, Brown Algae, Blue-Green "Algae"/(Cyanobacteria)Diatoms, Brown Algae

Related FAQs: Green Macro-Algae ID 1, Green Macro-Algae ID 2, Green Macro-Algae ID 3, Green Macro-Algae ID 4, Green Macro-Algae ID 5, Green Macro Algae ID 6, Green Macro Algae ID 8, & Caulerpas, Green Macro-Algae 1Green Macro-Algae 2Green Macro-Algae 3, Green Macro-Algae 4, Chlorophyte Behavior, Chlorophyte Compatibility/Control, Chlorophyte Selection, Chlorophyte Systems, Chlorophyte Nutrition, Chlorophyte Disease, Chlorophyte Reproduction/Propagation, Marine Algae ID 1, Marine Algae ID 2, Marine Algae Control FAQs II, Marine Algaecide Use, Nutrient Limitation, Marine Algae Eaters, Culturing Macro-Algae; Controlling: BGA/Cyano, Red/Encrusting Algae, Green Algae, Brown/Diatom Algae

What is growing on and near my live rock?     10/12/18
Hi folks,
<Hey Shawn>
I have been using your site for many years and it has always been a blessing and answered every question I had!
<Glad to know it has helped you that much!>
I have a 90gal tank with quite a bit of live rock and very few inhabitants currently (few small snails). Getting the tank ready to stock once again and (outside of some unwanted algae), I have some things that started growing that I have not experienced before. I can't seems to find exactly what these tree/twig looking things are that are growing on and next to my live rock. Kind of remind of Mangrove roots here in FL. Here is a pic of them in the tank and one that got temporarily de-rooted as I was
cleaning tank and bedding while readying for next participants.
<This is some kind of calcareous algae, looks like Halimeda incrassata.>
Regards, Shawn
<Have a nice day. Wilberth.>

Algae id      5/11/18
Im cycling a marine aquarium and this algae has grown i can id if it is Bryopsis, Derbesia or something else.
Are you able to help?
<Does look like both these noisome genera... I'd be reading; considering "nuking" (bleaching) this system... to start over. Bob Fenner>

Marine algae ID?      4/26/15
​Hi, I was hoping you could help me with an algae ID (see attached photos).
This popped up all over my new (only about 2 month old) saltwater tank. Is it Bryopsis? Or something else?
<The latter... but not able to tell w/o microscopic examination... either a brownish "green hair algae" (there are hundreds of species) or if it feels very slimy, a Moneran (BGA)>
I started from dry rock and added 1 piece of live rock from a fellow reefer, and all was fine, no algae. Then I added 2 coral frags and suddenly there's algae everywhere. Not sure if that's just coincidence or if a spore came in on one of them.
<Mmm; possibly a factor... though such spores can and do come in via the air, tap... Propitious circumstances (ones that favor them)... too much nutrient, not enough competition, predation, favorable lighting for less noxious forms... the usual>
I​ just wanted to see if I could get an ID before I try to treat by raising magnesium, which could help if it was Bryopsis, but would kill the snails.
Thank you!!
<Do the usual read through WWM re algae control; or hey! I have a newer e-book and direct to print (Create Space) on the topic. Bob Fenner>

Can I get an ID please?       3/6/15
<Ohh, that green algal mess above the Zoanthids?
Looks to be either Derbesia or Bryopsis. Please see here re:
Bob Fenner>

Caulerpa Taxifolia?   Not    12/12/14
I purchased some Chaetomorpha from my LFS and placed it in the 2nd chamber of my Biocube. I am using reverse daylight with it and found another type of algae growing on the wall of the chamber when I checked it recently. It looks like Caulerpa Taxifolia to me but is growing in clumps instead of on a vine like I see in images. Can you verify if this is indeed Caulerpa Taxifolia or some other type of algae? If not Caulerpa Taxifolia, is this some other type of nuisance algae?
<Your image is too large, but also too poor to make out w/ any confidence.
Please re-try; send a better pic... more resolved, of a few hundred Kbyte size>
Bob Fenner>
Thank you very much for your time!

Re: Caulerpa Taxifolia?       12/12/14
Apparently uploading the pics to Outlook is degrading them.
<Nope; same crappy pix, and you sent five and a half meg.s this time. JUST READ ON WWM
. BobF>
I zipped the files and sent them to my husband as a test and he can see them fairly clearly. I am recharging the battery on my camera which should work better than my phone so if these don’t work for you I'll try again with the camera. By the way, the pics are all at least 1 MB in size. Sorry for the confusion and let me know if you still need better pictures.
Thanks so much!

Re: Caulerpa Taxifolia?    12/14/14
I am now educated on the way to submit pictures. I apologize for any inconvenience! Each picture is 600 x 800 pixels and is under 150 kb each. I took these with a real camera instead of the cell phone so hope the resolution is good for you now. I placed them in a zip file to maintain their resolution.
At least I had good grammar and punctuation in my emails
Thanks again for your patience,
<I do think this is one of the many species of Bryopsis. Please see the coverage of species on AlgaeBase:
Bob Fenner>

Algae Identification; and Elysia use      12/10/14
To whomever this may concern,
I have a bit of Bryopsis and my tank is quite mature (8 yrs old) with plenty of algal types so I decided, after much research, to try my hand at a lettuce sea slug ( Elysia Crispata). I know many are marketed as eating Bryopsis, but am aware that there can be significant individual variation in diet with some preferring other types of macros.
<A valid concern>
My new lettuce slug, Berg, seen in the photo attached, has had no desire to eat any of my Bryopsis.
<Better choices about>

I have literally placed it there, like leading a horse to water, on numerous occasions, just to watch it crawl over it. I have been
vigilantly observing it to try to deduce what other algal types it might be eating so that I can provide for it by proactively seeking those out. So, I have this interesting algae I would like to try to ID ( pictured below).
It looks like little green translucent-ish stalks or stems. They are kind of stiffish and offer some resistance when you press on them, after which they bounce back to their original position. I put Berg next to it to see if it would eat it, and it did. So it seems I have successfully "identified" something it will eat, so now I want to actually identify it so I can get some because the tiny tuft I have ( pictured) wont grow fast enough to sustain Berg I think. What do you think it is?
<Mmm; can't quite make it out to be very sure; even after cropping, trying to optimize the pix... my guess is on Valonia macrophysa>
I also am trying to get my hands on a few other macros they have been documented to eat to try those out but thought this was a great lead for the time being. Thank you for the help and I very much appreciate your time and your thoughts on how to go about identifying the type of algae I have here.
<Had a few classes in Phycology... there are guides, dichotomous keys of use... need a simple microscope. If you get one (they're cheap, available) with a USB hook-up, send some high res. pix along. Bob Fenner>

cropped and enhanced.

Mysterious algae ID, please!     10/7/14
Hello. It has been months since cycling has completed, and nearly all of my algae has disappeared except for one variety that I have never seen before. I have some fuzzy stalks remaining of some kind of macroalgae that I cannot find an ID for anywhere. These are shaped like a pipe cleaner or a bottle brush, and they grow to a maximum height of between one and two inches. They are not rigid, and they sway in the current. It is not overly invasive, and I can keep it well under control by manual removal if I wish, so I would not call it a nuisance algae even if it is far from being decorative. My Cerith snails and my troches snails do not seem to be interested in it at all.
<A good clue>

Thanks in advance for any help that you can provide.
Kind regards,
<My guess is on the genus Caulerpa... perhaps a nutrient starved (and overgrown by other algal groups) variant of C. taxifolia. I would continue to do the manual removal you mention. Bob Fenner>

Re: Mysterious algae ID, please!     10/7/14
Thanks for the reply. I am slightly familiar with C. taxifolia, but this is very different because it is not fern-like. The "leaves" radiate out from the central stalk so that the plant is arranged somewhat like a bottle brush. Think of the size and shape of Neomeris (although a little taller) but not compact and calcified, but with brush-like leaves.
Thanks again,
<Mmm; Steve, could/would you try a close up that's a bit better resolved?
I'll send this about
Re: Mysterious algae ID, please!     10/7/14

Is it possible that this is some type of Dasycladaceae? Particularly Batophora or Chlorocladus?
<Mmm; your pix appear to represent a two-dimensional (flat) organism...
These genera are circular, three D>
For some reason this reminded me of Neomeris, and I just looked at others in the same order, but I have no idea if I'm on the right track. Please let me know what you think.
<That better pic please>
Re: Mysterious algae ID, please!     10/7/14
<.... are these Pennatulaceans? B>
Re: Mysterious algae ID, please!     10/8/14

Thanks for the response. I will take a better picture tomorrow, when the lights of the tank are on, with a better camera.
<I thank you. BobF>

Re: Mysterious algae ID, please!    10/8/14
Here is a better photo. Let me know if this isn't adequate.
<Ahh! These are like bottle brushes I see in this pic. Am much more inclined to agree w/ your guess re Batophora
Thanks again,
<And you for the follow-up. Bob Fenner>

Re: Mysterious algae ID, please!    10/8/14
Hi again, Bob. Here is another bit of algae that I have in my tank.
I believe that it is from the same family. Very strange!
<Indeed. B>

Bryopsis I.D.
Do you happen to know what species of Bryopsis this is?
<The greenery to the right and left of the Aiptasiid? Nope>
Because I checked algaebase.org and It doesn't match any of the 43 Bryopsis photos they have posted and I didn't have any luck searching online either. The guy at the pet store said it most likely came in from the Caribbean but he didn't know the exact species. Not sure if that helps narrow it down but thought I'd mention it.
<Don't recognize it/this period. Do you have access to a 'scope w/ a USB attachment that you might make some close up images?
Bob Fenner>

Re: Bryopsis I.D.
I don't have a scope but I'm certainly willing to attempt some up-close and clearer photos with my camera for you. Or do you need footage at a microscopic level?
<Closer is best... one macro, a few at a few tens of power magnification>
How powerful a scope would it need to be?
<As above>
If their not too pricey I might get one.
<Oh! Do see my shameless plugs on WWM re the QX3 scopes by Intel/Mattel...

What to do about the moss/algae     3/19/14
This is a pic looking down over my 29 Biocube. Can you identify my bright green leafy plant?
<Halimeda sp.>
I like it and my little gumdrop gobies love to hide in it. Can I prune it back a bit?
<If you like.>
And I have developed an overgrowth of moss/algae.
<Looks like a Derbesia sp. Commonly referred to as hair algae.>
Not sure why or how. I'm scrubbing it off weekly and pulling it out in tufts. Are my lights bad?
<Spectrum shifts in old bulbs can contribute to growth.>
Everything was moving along fine till about 2 months or so ago. Now I have this miss everywhere. My parameters are right where they should be,
<Likely due to the algae consuming excess nutrients.>
so all I can think is it has to do with my stock light in the Biocube.
(I've only had the tank for about a year, and it was new when purchased)
<T5s generally need to be replaced every twelve months. Halides every six months.>
I have Chaeto in the back, and I also use a small phosphate filter in the middle chamber. So, I'm not sure what causing the moss.
<Excess nutrients and possibly spectrum shift from old bulbs.>
Should I go to my LFS and get a few snails? Turbo?
<Pinpoint what is fueling the algae and remedy. Adding a predator is simply a band-aid.>
Thanks for any help you can provide.
<Quite welcome, Jordan>

Live Rock Growth ID     6/26/13
I noticed some random growths on my live rock and I was wondering if you would help me identify what they are?
<Mmm; yes>
 I was worried it might be some type of Aiptasia but i didn't see any pictures that matched. Also I was wondering about the coarse green stuff is and why there are hard bubbles forming in the middle of it. Is this something I should be concerned about?
<Quick metabolism... amongst mostly filamentous green algae. Not problematical.>
It seems to be localized to just on piece of live rock.
<The other two pix show Syconoid sponges; search on WWM re... Not an issue either. Bob Fenner>

Algae ID, 'scope, sample, rdg.     5/29/13
Any ideas what this is? It's fuzzy and very moss-like. I have a bit of red Cyano on my substrate and figure whatever this other stuff is it'll compete for nutrients with the Cyano. It's only growing on the back of my tank and the fish don't seem to be interested in it. Should I remove it, or just leave it be?
<Likely a large mix of green/s, blue-greens, Protists... Need to sample and go over w/ a 'scope. I'd remove a good deal of it with a scraper and vacuum every water change. Bob Fenner>

Algae Question Identification, and control    3/22/13
Hi there.
<Hi David. Jordan with you today.>
  Wondering if anyone there knows what type of algae I have  in this picture and what the best clean up crew suggestion for it is.
<Appears to be Caulerpa verticillata. I have read reports of some species of Tangs and Rabbitfish eating it but they are few and far between. I would recommend manual removal. Remove the rock and scrub with a stiff brush. Be sure to remove all of the algae, including all rhizoids/rhizomes, and rinse with clean saltwater before adding back to tank. This will likely take multiple attempts before it is successfully eradicated.  Hydrogen peroxide dips will kill it, but the dip will kill all other life as well.>
 I  have set up a new tank and just finished my cycle with Florida live rock and this stuff is starting to grow out of control.
<That is what Caulerpa does.>
 I am ready to add my  cleanup crew but need to know what will conquer this stuff the best.   I appreciate any help!  I have included some pictures  below.  Thanks!
<Quite welcome.>
  David Rudman
<<Well done Jordan. BobF>>

Re: Algae Question Identification    3/22/13
Thanks Bob!
David Rudman
<Welcome David. BobF>
Re: Algae Question Identification    3/22/13

Jordan said Caulerpa verticillata.  Which do you think is more likely the match?
<I believe his is correct. B>
Re: Algae Question Identification     3/22/13

Just Googled pictures.  It definitely is Caulerpa verticillata. 
<Ah yes>
David Rudman

Hi can you help me out please.  11/22/12
<Hello Grant>
 this is my first saltwater aquarium I've had it for 5 days it's 400 liters and roughly 20-30 liter sump running a skimmer and heaters to 24 degrees (Celsius). Yesterday I added live rock after achieving a 1.024 salinity<Specific Gravity> and was wondering what is happening on them i.e.: good or bad.
I'll attach 2 pics and hopefully get some answers, after searching the web I candidate find any info on what I'm describing or am possibly phrasing it wrong.
Is the first picture coral or something else?
<Palythoa, "good".  http://www.wetwebmedia.com/zoanthid.htm >
 On the second picture are these pods/bulbs good or bad the seem to be appearing really fast.
<Bubble algae, "bad".  http://www.wetwebmedia.com/BubbleAlgCont.htm >
My live rock has only been in the tank 24 hours. My water readings are as follows pH.=8.2  k.h=196.9  ammonia=0.50  nitrate and nitrite are zero calcium=380 and phosphate=0.25
Any help will be appreciated.
Thanks Grant.

Satellite Dish looking thing 7/10/12
I have a really weird thing growing in my Marine aquarium. I am unable to send you a picture directly but can give you a link.
http://www.kyreef.com/forum/attachment.php?attachmentid=1011&d=1341833804  I have looked everywhere looking for an identification and can find nothing.
It would help if I knew approximately what I was looking at. Here is another picture.
<"You are not logged in or you do not have permission to access this page.
This could be due to one of several reasons:">
 If those don't work try this one
<I can access this page but no picture is displayed.>
 It appeared after some new live rock but appears to be growing out of the sand. It is on a stalk about 2 inches high and is only 1-2 cm across the disk in the pictures. It is green and fluoresces blue around the disk under actinics. No fish or inverts bother it. It does not react to light changes like a feather duster or coral. Thank you in advance for any help.
<Possibly a mushroom or macro algae but without a picture this is just a shot in the dark. >
Re: Satellite Dish looking thing 7/10/12

Sorry I have attached the files now. My brain wasn't working when I sent that email.
<Pic definitely helps but it is quite small. It appears to be Acetabularia crenulata aka Mermaids Wine Glass.>

Spider-like eggs    5/1/12
I have several spider-like eggs on my LR. Any ideas?
<Mmm, looks like Valonia sp. to me. See here: http://wetwebmedia.com/greenalg.htm
Bob Fenner>

algae ID    2/9/12
Hi! I have these hard green leaf like things growing all over my tank. They seem to just stand up and grow all over, but I have no idea what they are and how I can get rid of them. I have looked through the macro algae ID pages and did not see anything like these. I have attached a photo of it.
Thanks for any help.
<Appears to be a Udotea sp.. See WWM, elsewhere re. Bob Fenner>

Plant ID: Halimeda €“ 2/14/12
<Hello there, Lynn here today.>
My tank will be running now for 2 years in May.  About a month ago when doing a water change I noticed these two little leaves growing out of one of my rocks.  These pictures are what it has turned into in a month€™s time.  What is it? 
<It appears to be a species of calcium-loving green algae in the genus Halimeda, aka €œCactus Algae€.>
Anything special I should do to care for it? 
<Although it€™s attractive, it seems to be growing/spreading fairly rapidly, so I would opt for manual removal.  For more information, please see the following links:
Take care, Lynn Z>

Algae ID question, and a few others. Stkg.   2/4/12
Hello, and thank you so much for providing a true wealth of knowledge for this fascinating hobby!
I have a 29g reef aquarium that is now several months old, and doing great!
Lights: 48watts T-5 HO, 1 10k bulb 1 420 actinic bulb.
Filtration:  Emperor 350, AquaC remora w/ Maxi-jet1200 (change carbon monthly so far in emperor)
Weekly water changes of 5 gallons.
Two blue-green Chromis
Two Black Ocellaris clownfish (mated)
One Flametail Blenny

One Maxi-Mini carpet anemone (also in picture.. has doubled in size in just under a month.. now 4" in diameter, I've heard these can reach 8"!?)
Two colonies of Xenia coral, my first and only coral in the tank.. doing great so far.
Four blue legged hermits.
Four turbo snails.
One peppermint shrimp.  (Bought him to help control an Aiptasia outbreak I noticed after some rock was added... he did a fantastic job and keeps the bottom looking grand.  I've heard these do well in groups, is it smart to add more or too much of a stress on the bio load?)
<I'd leave one as a singleton here>
Untold numbers of Nassarius snails (started with four, but they seem to be reproducing rapidly, should I be worried?  Small ones keep cropping up, but my sand looks great.)
Water parameters:
8.0 pH
12 degrees dKH
440 calcium
0 ammonia
0 nitrite
0 nitrate (finally at 0 after a few weeks of it still being on the charts, assuming my water changes are whats helping)
.25ppm Phosphate (from the tap water I use, undoubtedly... but everything seems fine?)
<Don't panic>
I test water weekly and things seem to be getting really stable.  My question today is regarding the algae in the photograph.  It came on the rock that I purchased along with my maxi-mini carpet anemone, and while it was originally covered in several types of algae, this is the only one that my snails/crabs do not eat.  It seems to be growing well with my lighting, and is growing at about a half inch a week.  I love the way it looks and have read on your website that macro algaes can serve a great purpose in helping export nitrates etc.  If this looks desirable to you all then I'd love to keep it, and then have a question as to when I should groom it.
<I'd cut this (Bryopsis) back weekly, while doing water changes; vacuum out...>
  I have heard algaes can go "sexual" (this seems to be a common reference with Caulerpa, which it looks like this is not) and is that something I should worry about?
  How frequently should this be trimmed back, and how much should I trim back? 
<Keep it confined...>
According to the visual algae ID chart, and the Algae ID FAQ's on wwm, I believe it might be Derbesia sp.
<This or more likely Bryopsis>
One last question while I have your ear.  Is my current stock list looking OK?  I am thinking of adding a Derasa Clam (the LFS has one that looks great and has looked great for several weeks) since I have heard that they are one of the easier clams to keep. Also, my final fish will perhaps be a Dottyback (strawberry Pseudochromis? or suggestions on any that would work well with my current stock)  Should I worry about the Pseudochromis not getting along with my blenny? 
<Yes; I would have just one or the other here. A 29 gal. volume is borderline in terms of stability, stocking options>
They have similar body shapes.  I'm also concerned that I might be overstocking at this point.
Thank you for any advice you can provide.
<thank you for sharing. Bob Fenner>

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