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FAQs on Marine Algae Identification 24

Related Articles: Avoiding 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: FAQ ID Visual Guide, Marine Algae ID 1, Marine Algae ID 2, Marine Algae ID 3, Marine Algae ID 4, Marine Algae ID 5, Marine Algae ID 6Marine Algae ID 7, Marine Algae ID 8, Marine Algae ID 9, Marine Algae ID 10, Marine Algae ID 11, Marine Algae ID 12, Marine Algae ID 13, Marine Algae ID 14, Marine Algae ID 15, Marine Algae ID 16, Marine Algae ID 17, Marine Algae ID 18Marine Algae ID 19, Marine Algae ID 20, Marine Algae ID 21, Marine Algae ID 22, Marine Algae ID 23, Marine Algae ID, 25, SW Algae ID 26, SW Algae ID 27, SW Algae ID 29, SW Algae ID 30, SW Algae ID 31, SW Algae ID 32SW Algae ID 33SW Algae ID 34SW Algae ID 35SW Algae ID 36SW Algae ID 37SW Algae ID 38SW Algae ID 39& Marine Algae Control FAQs 2, Marine Algaecide Use, Nutrient Limitation, Marine Algae Eaters, Culturing Macro-Algae; Controlling: BGA/Cyano, Red/Encrusting Algae, Green Algae, Brown/Diatom Algae   

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Marine Aquarium Algae Control

by Robert (Bob) Fenner

Identification 10/15/08
I am trying to find out if this pinkish/red stuff is a type of algae or a sponge & how to get rid of it. It started on my egg crate & is moving to my frags.
<Looks like a form of BGA. Read here for information on ridding yourself of this stuff: http://www.wetwebmedia.com/bluegralgae.htm. Welcome, Scott V.>


Re: Identification 10/16/08 Thank you for replying. <My pleasure.> It is not Cyano. It is about the color of coralline algae. <I still do believe Cyano to be the ID, the color is just in the name; comes in many forms.> This is what it looks like dry. http://i159.photobucket.com/albums/t135/BibleSue/IMG_0351.jpg http://i159.photobucket.com/albums/t135/BibleSue/IMG_0352.jpg This is what it looks like right after pulling it off. I don't have large amounts since I took everything out & scrubbed it off the egg crate & picked it off the corals Sat. night. It is already starting to grow back. <Indicative of BGA.> http://i159.photobucket.com/albums/t135/BibleSue/IMG_0353.jpg http://i159.photobucket.com/albums/t135/BibleSue/IMG_0346.jpg <A 'quick' jaunt through the Marine Algae ID FAQ pages (there are 25 of them!) will show you similar forms of BGA. A microscope of moderate power will tell you for sure, the BGA will lack discernable nuclei. Anyway, the eradication plan is the same either way. Scott V.>

A little identification help please -- 10/13/08
Hello crew,
I've had this algae/plant growing in my 150 reef tank for quite a while. Very pleasant looking but starting to spread more than I'd like.
<Mmm, yes>
Neither my tang, blennies, hermits or snails seem to munch on it.
<Not very palatable... to much of anybody>
Could you help identify it
<Mmm, likely a species of Derbesia>
for me and suggest a way to lessen the spreading.
<See WWM, the Net re this name... and likely Bryopsis... both "treated" about the same... best by competition, denial of nutrients... a few approaches to these...>
(I have multiple corals so limiting the lighting would probably have to be minimal). I'm running the PhosBan reactor so there's not a phosphate problem.
Also, I've worked with you (Bob) before so my water quality is "up to snuff." Over the past few months I've replaced all lights, drained water from frozen food and done weekly water changes to keep nitrates very limited.
Thank you,
Greg Esposito
<If there's room, you might try other predator groups... maybe a Siganid... S. stellatus if you can find one... BobF>

A little identification help please - follow-up... Grn. alg. contr.  10/15/08 Hello again Bob, <Greg> Thanks for the info below regarding the Bryopsis/Derbesia problem. I've done more research on your site trying to get a good handle on the specie and ways to eliminate/control it. <Can be persistent!> I wanted to run by you what the LFS just told me when I stopped in to get a fresh batch of C-Balance and look for Caulerpa. <Mmm... a bit to say re both... the Wilkens, nee TLF product is fine, but I'd definitely pass on this genus of Chlorophyte (folks do try to use mainly C. verticillata to outcompete Bryopsis et al. for you browsers)... reasons gone over and over on WWM> First, let me say that my LFS (The Living Sea) has been around for quite some time and I've generally found the owners to be pretty knowledgeable. <I also have heard many good anecdotes re> That said, I asked them today if they were familiar with the algae to which they grimaced and quickly said, "you'll never get rid of that algae"... <Heeeeeee! Man, that's a dire statement!> "we've never found anything that would eat that"..."it will be the last thing to die in your tank." <Along with terrestrial cockroaches? Heee!> I left the store with the options of: 1) Take out the affected rock, wash it and scrape off the first layer in hopes of getting it all. But, if I miss one strand of the Bryopsis, it will all grow back. <May be> 2) Take out the affected rock and let it dry/die. <Another approach> 3) Leave the tank "as is" and expect to have to shut the whole thing down if the algae spreads. <Sheesh!> Are things that bleak? <Mmm, nah> My 150 was born in October of 2006 complete with Current Orbit Halides/Actinic T-5 lighting system, protein skimmer, PhosBan reactor, UV sterilizer and chiller. I run carbon, too, and my refugium is stocked with Chaetomorpha sp. per your advice. 35 gallon water changes are done weekly or bi-weekly....mostly bi-weekly. I do have a R.O. system, make my water and perform all tank maintenance. Specs: Salinity: 1.025 Nitrates: 10 or less Phosphates: 0 Ph: 8.2 to 8.4 Alkalinity: 6.5 to 7 Calcium: 440 to 460 Temp: 75 to 77 Actinics run 11am to 8pm and halides run 12pm to 7pm. Refugium lights on from 8pm to 11am. Stock: Most of my corals are large (8 to 12 inches) including Leather, Elegance, Frogspawn, Bubble and Toadstool. 6 inch Sail fin tang, 4 inch Copper banded Butterfly, 2 medium Chromis, Male and Female Maroon clowns, Lyre tail Anthias and 2 Lawnmower Blennies. Also, a lot more snails and hermit crabs than you would prefer...as you've told me before. <Mmm, I'd still try the Siganid, possibly some Sacoglossan: search: what eats Bryopsis> I've attached a picture of my tank, too. <Ahh! Very nice! What a beautiful setting altogether! Something right out of "Beautiful Aquariums, Homes and Gardens" magazine!> Thanks so much! Greg Esposito <Don't despair Greg... I've seen the end of the world... this isn't it. Bob Fenner>

A little identification help please - follow-up 10/15/08 Whoops...also forget to mention I have 6 maxi-jet 1200 powerheads hooked up to a Wavemaster machine. <With such a fancy setting, I thought you'd likely be vested in Tunzes! B>
LOL. Maybe I should add Tunzes as our fish and corals deserve the very best we can offer them. Thanks for the guidance, as always.
<Welcome my friend. BobF>

Algae I.D. 09/27/2008 Greetings Crew, <<Good morning, Andrew today>> Thanks for the great site! I have looked high and low for information on this algae but I can not find it anywhere. Forgive me if I've simply overlooked it. Thanks in advance. <<Corallina elongata I would suggest. Please do use your search engine for plenty of info on this algae>> John T. <<Thanks for the questions, hope this helps. A Nixon>>


Re: algae?    9/20/08
My last reply may not have sent, I will try again from here then through my work email.
<Okay... did you get my response? Oh, I see it below>
Live Stock= Regal Tang, Percula Clown, Flame Hawk, Mandarin, Scooter Dragonet, Yellow Blue Spot Goby, Two Pajama Cardinals, Long Tentacle Anemone, Christmas Tree Worm,? lost a Purple Tang and Royal Gramma that had been in there about a year.? About 10 each of Hermit Crabs and Snails.
One Acropora frag, Two Montipora frags, Two Small LPS - (Frog Spawn and Torch Coral), two tree? Sponge (not doing well at all now),
<Rarely do in such settings>
Coco Worm (Christmas Tree Worm), Purple Gorgonian, One small Ricordea mushroom coral, small amount of star polyps. All of this never seems to be growing very well either,
<Typical Cnidarian incompatibility issues...>
like not at all (just surviving).? Feeding it DT formula every third day, with pump off for 20-30 minutes.
I have a 10 mb video file of the tank and slime.? I will have to send that from home, here is an attached photo from that video.
<A mix of decomposers that are "best situated" to your present circumstances. Again, the best means of disrupting them is to alter the conditions in the system as stated ayer... Bob Fenner>

Diatoms?    9/20/08
Hello, and thank you for your time,
<Howdy, welcome>
As you can see from the photos, I have quite a bloom of some sort of algae.
I was initially suspecting that this is a diatom bloom.
<Mmm, nah>
However, there are a couple of characteristics that make me question my initial assumption.
This "bloom" seems to be completely light dependant. The sand is almost perfectly white every morning when I turn on the lights, and then within a couple of hours reaches this ugly brown color. The algae is somewhat filamentous, but does not appear to be "slimy" as I have seen Cyanobacteria appear to be. It seems to be acting like a glue to the sand (making is clump together); as you can see from the photos of the tank ornament, it is nasty stuff. The "clean" photo is immediately after a turbo grazer had a feast, and the other tank photo is only a few days later. I didn't think that diatoms were dependant on light,
<Mmm, yes they are>
but this stuff seems to be. My tank parameters are: ammonia: 0ppm, nitrites: 0ppm, nitrates: 5-10ppm, phosphates: 0ppm,
<Mmm, do consider that the algae et al. here can/does remove/concentrate nutrient, making it unavailable in the water for tests>
calcium: 300ppm (this is lower than I would like, but I have been battling high alkalinity from using tap water).
<See WWM re possible paths here... easily done>
The steps that I have taken to solve this problem are: switched from treated tap water to R/O water, started using Phosban (with the hopes of removing any silicates), water changes only seem to help for a day or so (and then they come back with a vengeance),
<Another clue>
and I have tried stirring the top layer of sand only to see the freshly exposed sand turn brown within a couple of hours. The lights are about 6 months old (260W of compact fluorescents)- do you believe that the age of these could be the problem?
<Mmm, likely secondarily>
The tank has been running for about 8 months without any of this algae, and now within the last month this stuff has taken control. I do weekly 20 gallon water changes, and my aquarium is 155 gallon with a 20 gallon sump.
<Do you grow macroalgae here? You should... or get another or larger sump/refugium to do so>
I, unfortunately, am using a SeaClone 100 skimmer (that never seems to function -maybe my entire problem?),
<A part of it at least. Again, see WWM, plan on, get a real skimmer>
a Fluval FX5 canister (cleaned weekly), and I am using Chemipure in the canister filter. My fish include: 1 hepatus tang, 1 Eibli mimic tang, 1 green chromis, 2 Ocellaris clowns, 1 marine Betta, 1 sleeper banded goby (he likes to spread this brown stuff all over the tank), 1 clown goby, 1 engineer goby, 4 large turbo grazers, countless Nassarius snails, 1 large brittle star, a colony of green star polyps, a colony of brown button polyps, and two stalks of pulsing xenia. I have the corals about halfway up the water column, and the algae hasn't made it that far yet, but now it is getting close and I need to act. Before this algae took over I was having great purple coralline growth, but now this stuff is over growing the coralline (as you can see in the photos of the tank ornament). I'm getting very frustrated because I can't seem to control this stuff. I have silicate and magnesium test kits coming in on Monday. Any advice would be greatly appreciated.
Thank you again for your time,
~William Millis
<Well, very likely what you are seeing, battling is principally BGA/Cyanobacteria... can be "fought" in a few ways... enhanced RedOx (via the skimmer improvement partly/easily, the culture of macroalgae)... I would also look into making a DSB in the added sump space... At any length, all is recorded for your perusal here: http://wetwebmedia.com/marine/maintenance/maintindex.htm
the third to last tray. Enjoy the learning, empowerment of knowledge gain, practice. Bob Fenner>

Re: Diatoms?
I am truly sorry that I forgot to include my PH value: 8.4,
<Fine, not a factor>
and I have completely covered the entire aquarium with blankets to eliminate the chance of ambient light from the room. However, this had no effect on the growth.
<Won't. BobF>
Thank you again,
~William Millis

Good Versus Bad Algae  9/18/09
hey guys,
After what i consider to be a nearly total catastrophe...
<... where are the spaces...>
Quickly...I live in Phoenix AZ and my AC went out. before i knew it My water temp was over 100
( lesson learned) I now have a chiller. My 65g reef died...everything..corals, polyps, leathers, anemones, paired clowns snails...EVERYTHING all except for my Yellow tang..God bless him. Anyway....I broke it down and restarted using the same live rock. 10-15% water changes every couple days for a few weeks...everything seems to be going OK so far. Water parameters are good. PO4 = 0, NO4 = 0 NO3 = 0 Ca+ = 500 PH 8.3 temp 82 degrees .
The coralline is seeming to spread nicely however There is a new addition...the Dark green algae you see pictured.
<This is actually, likely BGA...>
At least I think that's what it is..there are several dime to quarter size spots scattered in the tank and if you look in the top right corner of the tank there is some lighter green growth. Is this something I should worry about? THANKS BUNCHES
<Mmm, I would read: http://wetwebmedia.com/algaeasfriend.htm
and the linked files above... till you understand what is going on, what your options (for control) are. Bob Fenner>


Purple Feather Weed? Could Be Feather Hydroids! 9/13/08 Hi Guys and Gals, <Hi there, Andrew> While snorkeling today (thank God it's warm enough to get in the water again!) I came upon this fascinating (to me anyway) feather-like organism. <it's neat looking, that's for sure.> I couldn't help but lift a small piece off the rock for an experiment in my 20Gal. <Were you wearing gloves at the time?> Tank is currently about 2 months old, cycled with 6Kg semi-cured live rock, and live sand. Ammonia, Nitrite @ 0, and Nitrate is at about 10 at the moment, <Just keep an eye on the nitrates, don't let them get above 20ppm.> temp steady at 26 Deg C, and salinity is 1.022 <Salinity's a little on the low end, but okay.> Stocking is 1 bicolour Dottyback, 2 tiny blue/green chromis, 1 even smaller yellow coral goby, 3 small hermits, and about 8 snails. All very happy in their current home. <Good> Which brings me to my actual question.... What the heck is it!? <I sincerely hope I'm wrong, but those sure look like feather hydroids to me (Family: Plumulariidae). If so, they're not the best addition to a system, to say the least. Also, after going in for a close-up, that red macro-algae on the right side of the rock looks very similar to a variety that can be invasive and very difficult to control.> I found it in full sun at a depth of about 9' (growing on a football sized tunicate) <Wow!> ..in a bed of sand held together with fine hair algae. It came away in a nice clump about 2" across. It now graces the front of a lightly stocked tank. Each "feather" is separate from the next, and grows just like a real bird feather would, <Yep> looking side on, you can see a single "tap" root about the length of the feather itself. <That long 'tap' root along with the unusual color is what's keeping me from being absolutely sure those are hydroids.> I'm pretty sure in between the main subject of the pic is some juvenile Dictyota, <It looks like a Rhodophyta/red algae of some sort, but I can't see it well enough to narrow it down further. Dictyota is a brown algae (Phaeophyte) that's usually green, yellow/brown, or even blue. I've never seen red. It could be something like Scinaia.> ..but cannot find any reference to the feather like growth (which I find most attractive), <I find it very attractive as well. By the way, I couldn't find any similar looking macro-algae in that color either - and I was hoping I would!> ..but am a little cautious of! <Good call! Hydroids can sting the living daylights out of you. Please see the information and species 'Gymnangium' half-way down this link (as well as associated links at the top): http://www.wetwebmedia.com/hydrozoans.htm Here's a good close-up of a feather hydroid. Note the similar, almost bumpy/broken appearance of the 'branches'. Those bumps are actually individual feeding polyps that have little stinging tentacles surrounding them: http://www.poppe-images.com/images/image_info.php?picid=929540 .> If you could help identify it, I would be most appreciative. <Well, I'm pretty sure those are hydroids, but I'm hoping Bob will confirm or deny.> I make an effort to Identify everything I can myself, <Good for you! Not only do you get the satisfaction of solving a mystery, you also learn quite a bit along the way.> ..but find it difficult to locate images on your site unless I know the name of the organism I am looking for. <See below> Is there an image library somewhere grouped in broad categories like fish, algae inverts etc. that I am yet to find on your site?? <Not a specific image library as yet, no, but it's been discussed. In the meantime, Bob has the site organized/sectioned off into topics that include many terrific articles with photos of representative species in the most commonly seen genera. Usually that will give you enough information to help narrow things down a bit. Here's the main page for marine topics: http://www.wetwebmedia.com/marine/index.htm . Just pick a subject, start with the articles for an overview (with photos) and go from there.> I would love to help myself in future where possible. <I'd try the above and/or use our Google search engine: http://www.wetwebmedia.com/WWMAdminSubWebIndex/question_page.htm > Thanks for your time. All the best. Andrew.
<You're very welcome, Andrew. Take care, -Lynn>

  Hydroid. RMF

Identification help...BGA 9/9/08 Heya Crew, <Hello Phil.> My tank has been up and running for 6 weeks. Being new to this hobby, I have no idea if what is in the picture is good or bad. <Not desirable, but common.> Please help by identifying the "growth" and "silvery" bubbles. Thanks. <It is simply BGA, Cyanobacteria. BGA is photosynthetic, hence the off gassing/bubbles. It is indicative of a not so great water quality. > -Phil <The link below will give you the low down on what this stuff is and how to eliminate it. Scott V.> http://www.wetwebmedia.com/bluegralgae.htm

Macro identification -08/05/08 I think this type of macro algae is Saw Blade Caulerpa <'tis so... as far as I can tell from the photo provided.> but I am not sure. I was hoping that you could help me out by identifying what kind of macro algae this is. <Best,
Sara M.>

New Print and eBook on Amazon

Marine Aquarium Algae Control

by Robert (Bob) Fenner

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