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FAQs on Marine Algae Identification 11

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 12, Marine Algae ID 13, Marine Algae ID 14, Marine Algae ID 15, Marine Algae ID 16, Marine Algae ID 17, Marine Algae ID 18, Marine Algae ID 19, Marine Algae ID 20, Marine Algae ID 21, Marine Algae ID 22, Marine Algae ID 23, Marine Algae ID 24, Marine Algae ID, 25, Marine Algae ID, 25, 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

Algae Or Cyano 12/22/06 Dear Crew, <Nicole> I'm sorry for bothering you during the holidays but I've got some green and red algae that is popping up all over my tank and I'm not sure what it is and what I need to do! <No bother, is what we are here for.> I've looked through your website and I'm not able to ID it; however, I do believe it may be Cyanobacteria. <Does not appear to be Cyano.  Cyano generally grows in sheets.  What you have is typical red algae quite common on developing live rock.> On the first, second and fourth pictures you can see these green chunks in the sand and green on the live rock.  The third picture has red "hair like" stuff growing on it.  I switched tanks (from 12 gal. Eclipse to 24 gal. Nano) approximately three to four months ago and do a 20-30% water change every three weeks or so with RO water. <Would be much better doing three gallons weekly.  It will help control the growth and limit spreading.  Do consider using a carbon/resin media such as Chemi-Pure which effectively removes dissolved nutrients from the water.> At that time I will drop in a balance block. <Would not use this.  Maintain pH/dKH with additives designed for this purpose.> There's also a lot of Bryopsis?. <Will pass in time with continued water maintenance.> I have a green emerald crab (that's turning white - adding iodine) that doesn't seem to be attacking that and I   was told it would. <Emerald Crabs are generally used in controlling Bubble Algae.  Will not make much of a dent in your type.  If you do not already have hermits and snails, their addition will help algae control also.> Anyway, would you please help me to identify these things and advise   me as to what I should or shouldn't do? <It is a pleasing effect in what I'm looking at.  I'd leave it alone unless it gets out of hand.  Watch your bio-load, keeping it low keeps nutrients low.> Thanks a lot and happy holidays to you all!!! <And to you, Nicole.  James (Salty Dog)> Respectfully,

Black hairline vegetation on LR  7/15/06 I had bought some new Fiji Live rock to add to a nano that I have at work. One of the pieces has this thin, bristly, black hair-like vegetation growing from it. Each one is about 3" long. I pulled a few pieces of this off and tossed it into my freshwater tank, they turned to a grass-like vibrant green and eventually died after a week or two. I brought that piece of rock home and put it in my larger 75 reef tank. It has since grown a bit out of control and is spreading very fast across my reefscape. I am worried that it is starting to encroach on some of my SPS and Zoa's. There is actually a colony of zoanthids that has these "bristles" growing in between each polyp, it's very strange looking. What are these, and should I get rid of them while I can? Thanks so much! <Very likely this is a Green Algae (my guess either of the genus Derbesia or Bryopsis... see WWM, Google's images re...). Hard to "get rid of"... though there are some techniques gone over on our site (Algae, Green Algae "Compatibility"...). If confined to one or a few rocks, I might consider scrubbing this material off... Bob Fenner> -Jeremy

Algae identification ... SW, sans pic    7/13/06 Hi crew! <Samuel> I read (painfully) through the 10 pages on algae control, learning much (but not what I was trying to find out!). I find it difficult not knowing even the common name of the algae I have. If you could ID it for me I would appreciate it! I am in the process of setting up a fuge so hopefully I can control the algae to stay in there. - but I doubt it! (: The algae is a deep purple/brown colour. It starts out as a thin mat on my substrate (primarily) and rocks (to some extent). Gas bubbles are very noticeably produced once the algae grows into a thicker mat. When it reaches this stage it can be peeled off easily (so apart from looking bad this algae is probably quite a good way of removing nutrients!). It looks somewhat like the algae in the picture at the top of this page: http://www.wetwebmedia.com/algcontFAQsMar.htm Thank you so much for your help! Sam McMenamin <Mmm... very likely a BGA... Cyanobacteria... if you can "scope" it under a few hundred power of magnification you'd be able to discern this to the Division level as a Moneran... Please read here: http://www.wetwebmedia.com/bluegralgae.htm and the linked files above... I would be devising a plan to reduce this noxious life form to unnoticeable level. Bob Fenner>

Re: Algae identification, Likely BGA  7/14/06 Thanks for that ID Bob! I guess I simply overlooked blue-green because I assumed it would be...well...Blue/green (not red/brown!!!) <Heeeee~! Comes in a myriad of colors!> I currently have only a small wrasse and one green Chromis in my 150 gallon tank so I doubt that overfeeding is an issue! (I am converting to small predator tank currently but this problem needs to be solved first!) However, recently my brittle star has taken to eating my smaller fish! (a Chromis and a blue damsel) <Ah, yes...> I was unable to find the Chromis so perhaps this is the source of nutrients? <Some...> After my old protein skimmer went to God there was a break of perhaps a month in which I had no foam fractioning (another thing mentioned in the article!) <Ah ha!> Now - to solving the problem! I think I have adequate flow (3 x 3000 litre per hour powerheads and one 2000lph powerhead in display tank with a 6500 lph sump pump with a separate 3500 lph pump for my large new protein skimmer) Oh...gallons - I think 3000lph is 750gph to give you some idea. <Yes> As I said I now have a large protein skimmer going (though not for longer than a week yet) and I run a 36W UV sterilizer. The article mentioned ozone as a good control method... I have an ozone processor which I used for two days before a slight smell convinced me I need to build a proper reactor before it is safe. (next school holidays I think!) Oh and I have been removing by hand whenever it comes back with little success! <Mmm, likely the UV is producing a goodly amount of O3... do you have a means of measuring Redox potential?> I run 2 x 150W MH plus 2 x 18W PC plus 2 x 40W fluoro actinics. I am adding some more light soon for aesthetics only but I believe this is enough light to favour other algae. <Yes> As I mentioned I am right in the middle of setting up a fuge which I hope - after reading the article - will deal with the problem before I add my harlequin tusk, magnificent Foxface, large clowns and snowflake eel! <Oh... yes... this should work out fine> I hope the fuge will solve all the worlds problems... ... ... <One at a time... with the occasional double-header to keep things interesting...> But just in case it doesn't do you have any more specific suggestions? <Mmm, keep your beer in a cool place... that's about it for today> Thank you so much! Now that it is ID'd I can start reading up I guess! Sam McMenamin <Thanks for this "further along" Sam. Bob Fenner>

Mystery Red Soft Coral ID ... actually a Rhodophyte   7/12/06 Hey crew, <Yawnnnn! G'morning> Thanks for all of your previous help, in your kind responses to my past letters, and in the awe-inspiring resource you provide. I'm currently at a loss as to identification of this lovely growth that has sprouted up recently. <Mmm... tis a Rhodophyte... likely a Nemastoma sp. See here: http://www.wetwebmedia.com/redalgae.htm> I purchased this colony of Ricordea mushrooms, specifically for the large mushroom visible in the pictures. Upon bringing it home, I found 2 other small Ricordeas on the rock, and shortly after, the main Ric split itself and formed a 4th. (The other mushrooms are visible about midway up the rock, just right of the main Ric, and below and to the right of the 2nd spot of the mysterious red growth). About a month after bringing home this beautiful specimen, I began to notice red 'bubbly' growth on the rock, in 2 spots that appeared to previously be a very dark crimson red coralline growth. Now, after 3 months, its becoming large enough to discern shapes and polyps on, and I know I've got something interesting on my hands, I just don't know what. <A red algae> The appearance of it reminds me of stacked shingles, as it appears to be a very dense 'pile' of translucent soft red. There are darker red spots, that are hard to discern in the picture, which present small polyps during the day. The upper cluster of the growth is about an inch wide, and about 3 inches long, with the lower growth being a patch just under 1 square inch. Any ideas? Thanks,
<Not to worry... Bob Fenner>

Pink Fuzzy/Hairy Algae Balls 7/10/06 Hi, <Hi> I have this pink fuzzy/hairy algae balls growing in my fuge. The furry balls attach to the walls, rocks, or Chaeto. It's the same color as pink coralline encrusting algae. Can you tell me what it is? <Most likely cyanoBACTERIA.  Methods of control available here http://www.wetwebmedia.com/bluegralgae.htm .> Here are some pictures. (In the first, you can see some on the sides of the glass and the rocks; the second is a close-up of some on top of the Chaeto.) Jason

Red "Turf" Algae - 06/11/06 Hello, I am going to be a bother again as I have yet another question. <<Alrighty>> I have noticed some red algae in my tank in a couple of locations.  The algae does not appear to be Cyanobacteria as it is not slimy but rather threadlike.  It is so far quite short and very attached to the rock...yesterday I tried pulling it off but it is nearly impossible to remove. <<Ahh yes, am familiar with this algae...quite tenacious/difficult to eradicate>> Is this something I should be concerned about? <<Depends...in my experience this algae does not encroach/grow upon sessile invertebrates, but rather covers the bare rock surfaces surrounding them.  However, it can limit growth of your corals by restricting their "spread" upon the rocks.  All in all this algae is less "unsightly" in my opinion than most of the other so-called nuisance algae, but you should still try to determine the source of/limit its growth>> Is there such a thing as red hair algae? <<Many types of algae...this short turf-type algae is fairly common>> I looked through your database of red algae but cannot decide from the photos what it could be.  Sorry for the lack of a picture but it is so short I'm not sure you would be able to see it.  Like I said before it is very short and very tough I have seen green hair algae and this appears to be more course than that. <<Possibly a form of Polysiphonia>> My water parameters are all good, except alkalinity which I have written to you about previously. <<This may be factor in your algae problem>> Ammonia 0, nitrite 0, nitrate 0, calcium 400ppm, temp 78, salinity 1.023 and phosphate less than 0.2 ppm.   Thank you very much, Ryan Nienhuis....please let me know if I am driving you nuts with all the emails. <<Nope>> Also I was told my poor alkalinity is probably due to hydrogen sulfide buildup in my sand which is about 3 inches deep. <<Mmm, I don't necessarily agree...but I do prefer a sand bed an inch or three deeper.  Also...increasing your pH and alkalinity through careful dosing of Kalkwasser may go a long way towards helping with the nuisance algae>> I was wondering if you could recommend some sand sifters for me, I do have a Trachyphyllia brain on the sand bed and don't want him getting covered up. <<I really like the dragon goby (Amblygobius phalaena) for this purpose.  And don't fret to much about the brain coral and sand particles.  As long as it is meant to be on the substrate (conical/wedge shaped skeleton) it will have mechanisms for dealing with a bit of sediment accumulation>> I also already have plenty of bristleworms. <<An excellent/beneficial detritivore>> Thanks again. <<Happy to assist, EricR>>

Red algae - 05/05/2006 I have had an issue with red bubble algae for sometime now. By searching the FAQ I initially thought it was Botryocladia. I now am not sure of this. Reasons being that in other responses it was said that many predators would feed on this and it would disappear soon. <Sometimes...> I have had the problem for nearly a year now and it is worsening. Though I do not have a picture of this I can tell you that it does not grow on a stalk or vine like the Botryocladia in pictures I have seen, but rather directly on the rocks, filters covers and even snail shells. I have tried manually removing the bubbles but while attempting this I popped a bubble and a gel was secreted. <... this is likely a blue-green algae... not a Rhodophyte> I can only guess that this is how the algae reproduces because it spread like bird flue after that. The best way I can describe the culprit is to say it looks like a strawberry. Any ideas or predator suggestions would help. <... do you have access to a microscope of two hundred plus power? Bob Fenner>

Agent Orange algae?   5/4/06 I have noticed brightly colored orange spots where I have red algae in my tank. My red algae is not taking over the tank and I like the look of it in the tank. I am a bit concerned that a new looking algae I have never seen before. <Might not be an algae> I have heard of CLOD <As in soil?> and was not sure if I should be concerned about this. I know it is rare in the wild even more rare in the hobby. I tried to photograph it but it does not come up on my digital camera. Any suggestions to photographing it will be welcomed. Thank you, Homerj <... some input is posted on WWM re such, and much on the Net... see there. Bob Fenner>

Strange Algae???  - 04/27/06 Hey guys,   Algae question-   I have an algae starting on one or two baseball size rocks.  It is red/maroon in color.  It seems to have a white under color around the exposed edges but it covers the rock completely, and as it took over the rock, it always appeared to be full and round with no rough edges.  It's very smooth and thick.  It has to be over 1/4" thick.  To the touch it feels like a stiffer Jell-O mold.  It is not bad looking but should I be concerned? <Mmm, I would not be>    It seems to be spreading a little.  I have searched over the algae pics and haven't been able to find any matches for this type.   Do you know of a good reference algae site with more pics?   <What I have is posted...> Could it be the Cyano or BGA? <Yes... even a sponge of some sort> What should I do to eliminate it if it is bad? <If concerned, you might remove the rocks, clean them, let them air-dry>   The substrate-Fiji pink-  I got from a friend that had it in a 65 reef for 4 years.  I also got a few rocks.   It was very dirty and neglected when I cleaned the tank, but I remembered a strange piece or 2 of slimy, floppy, mushy, thick maroon, kind of pail, 3" long, Baby Ruth size (insert Caddyshack joke here!) <"You get a bowl of soup with that rock?"> algae thing that was pretty gross and went straight in the trash!!!  Could this be a cleanly molded version of that??  Is this a mold?   <Perhaps times dos>   As always, thanks for you contribution to our hobby!   This site always proves invaluable for it's vast reference information.   Thanks,   Randy <I would not be concerned. Bob Fenner>

Black wispy hair slime... BGA   4/21/06 Hello guys, I'm in need of some help! I've had a new saltwater aquarium running for about four weeks now, and I've got some very interesting and gross growth on top of the substrate. <Very common>   I've read through most of the letters from people regarding brown algae and even seen some of the pictures; none of these seem to match what I've got going on (please see picture). It's like a fine black/Smokey/wispy/hairline-slime covering my sand. <Yes... assuredly a type of Cyanobacteria... BGA> Even when I siphon the sand bed it just stirs up the gunk and it comes right back to the sand surface.  In my 55 gallon I've got about 35 lbs of live Lalo Rock from LiveAquaria.com that I cured for two weeks, 60 lbs of Fiji Pink Live sand, 6 small hermit crabs, a tiny horseshoe crab, two emerald crabs, a peppermint shrimp, a Pacific Blue Tang, and a Royal Gramma.   <You should (have) waited on these fishes...> I've been really careful about overfeeding the fish, and have probably been underfeeding, if anything.  I'm using compact fluorescent (2x65w actinic, 2x65w 10,000k), I'm running 3 powerheads, a Remora Pro skimmer, a canister filter <Read about these... not great for use on most marine systems> with BioMax media, and I have two 150 watt heaters.  The skimmer is skimming some good stuff, NH3=0.25ppm, NO2=0, NO3=0-2.5ppm , PH=8.2-8.3, Temp is 76.3º, SG= 1.022. <I'd raise this to 1.025>   I've been doing water changes weekly.  A couple things that I did that weren't so smart:  1. Add the two fish to my aquarium, I didn't really want them but my boss was going to flush them if I didn't take them from him. 2. I added reef crystals directly to my aquarium about a week ago because the salinity was low (I immediately felt like an idiot, I'm sure that I should have added an aqueous version of the salt mix to the tank). My boss also gave me about 15 lbs of live rock that I no longer have in my tank after noticing about 15 Aiptasia (that's why I have the shrimp) and a plethora of pink bristle worms on and in the rock.  I don't think that any of the Aiptasia made it to my new live rock, fingers crossed.  Anyways, I need some help.  Thanks for your time, and I've really appreciated all that I've already learned from the website!  Matt <This too shall likely pass... but more aeration, circulation, growing other types of algae... Please see WWM re Cyano control: http://www.wetwebmedia.com/bluegralgae.htm and the linked files above. Bob Fenner>

Brown algae ID, Anemonefish egg fertility, H. crispa repro.    4/21/06 Hello, <Hi there> I have had some type of algae in my 75 gal reef tank for about a year now. It has been slowly but surely spreading everywhere in that time. It is brown, and sometimes it is plating, and other times it is encrusting. It usually spreads in a round shape, and kind of has the texture/feel of cartilage. <I see it> It is very hard to remove, and has a slimy white fuzz on its surface. It wasn't really a problem at first, but is everywhere now. I don't have any other algae problems, and i have Chaeto in my fuge. I will attach a few picture to help with an ID. My emerald crabs don't eat it, and i would really like to get rid of it. <The one pic looks like Peyssonnelia. See here: http://wetwebmedia.com/redalgae.htm> Also, my orange percula and my black ocellaris have laid eggs together and take turns guarding the eggs. there are about 50 and they are orange with a silver dot in them. How do i tell if they are fertile? <Wait and see if they hatch out> It is hard to get a good look, because they are under the edge of their sebae. <Natural> Lastly, i have been looking for quite some time, and i can't find anything on the reproduction of sebae anemones. I heard that they cannot reproduce asexually, <Mmm, not so... do leave buds behind, undergo schizogyny...> but there is a picture of one doing that on your site. If this is possible, how do i get mine to do that? Where can i find more information on this. <See Anthony Calfo's works on "coral" propagation> Thanks in advance for all the Dan
<Bob Fenner>

Unknown algae, not useful message    4/14/06 Hi all, I know your all busy, love Anthony and Bob's books, and have started on their collective works. Have had a new algae growth and was wondering what it was. It appears harmless and to be a macro. It is fairly slow growing and I have seen some pods taking to it.   Also have a 6-8" tall Sea Grapes plant growing. I have read mixed reviews on it and was wondering if it was a problem. I think it looks nice and is conveniently growing right in the center front of the display. If needed I will get rid of it. <Not a question... Caulerpas are covered on WWM> One more quick question, I have a brittle star that I have had for about 6 months. It is the only one in the tank. It's about 10-12" tip to tip. About a week or so ago it has produced an offspring. I haven't found any info on asexual reproduction of brittle stars, but I have a new addition none the less. It has been wrapped around the central disc of the parent since then and is growing. Could it actually be some sort of hitchhiker predator of my starfish. Well thanks for all your work, it is a great service to many newcomers like myself. Here is a link to my pics of all three questions on a Yahoo group that I am learning from as well. http://ph.groups.yahoo.com/group/reefcity/photos/browse/a80f Thank You, Rick <Not a useful link. Bob Fenner>

Coral and Algae ID   3/15/06 Hi Crew! <John>     Just a quick question if you please.  I have attached the picture as well as insert it into this mail.  First, can you tell me what the coral is in the yellow circle under the mushroom corals?  It stays retracted like that during the day, but seems to "bloat" when the lights go off at night. <Perhaps a juvenile Mussid... can barely make it out> It has grown a little in size since the rock was placed in the tank a little over two weeks ago.  Also, is the object in the second circle and pretty much all over the rest of the rocks BGA? <Yes, of some sort> At first, I know I am going to sound like a newbie, but it is okay, because I am :), <No worries> I thought it was red coralline algae.  However, when cleaning my tank today I noticed with a little effort that it can be scraped off an it only on the parts of the rock that receive direct light.  It appears no where else in the tank than on the live rocks.  I do 10-25 % water changes weekly (With R.O water). I have been adding calcium and strontium (Sp) to the tank as well as Iodine for the skunk cleaner shrimp. My levels are all zero with the exception of my nitrite which this week was at .25 ppm. <Mmm, this is a clue... should be zip> My ph is 8.3 .  I am also using a Berlin Airlift skimmer that is one of their in-tank models.  That also gets cleaned weekly to insure proper operation. Thanks for the assistance! Oh yes my SG is 1.023 Thanks! John <Do give the articles, FAQs files on BGA, Algae Control a read over on WWM. Bob Fenner>

White Algae?  - 03/13/2006 WetWeb Crew... This is the fourth tank I've gotten going from the ground-up [ with many past successes due in large part to WWM :-) ], and I've never seen this one before... It looks like green hair algae, but is white (at least under my heavily blue-tinted T5's.)  Is this just common hair algae? <Mmm, looks like a form of BGA...>   My LR has been cycling for four months, and was just moved into my display tank last week. Nitrates are <5ppm, Phosphate is undetectable on consumer kit, Calc is between 350 and 375 ppm, Alk has been between 8 and 9 dKH, salinity is stable at 1.023, and temp is stable at 76.5-77.0 F. I've Googled WWM, ReefCentral, and Reefs.org, and haven't found anything quite like this algae I have growing on my LR. Any thoughts? Thanks, Sean Photos: http://reefcentral.com/gallery/data/561/17595needIDalgae_03122006_1.jpg http://reefcentral.com/gallery/data/561/17595needIDalgae_03122006_2.jpg <No worries. Will cycle out likely in a short while. Bob Fenner>

Re: Caulerpa query   2/24/06 Hi Bob, <David> I an trying to resend a pic of the Caulerpa and also of the unidentified algae. <Got them... both appear to be Caulerpa spp.> I am one of those who seen to have a problem getting queries through with attachments so we'll see what happens.  I have searched WWM for an ID on the second algae to no avail. Thanks David <The second may be C. pinnata... See the Net or Baensch V. 1 Marine Atlas, p. 302... perhaps C. flagelliformis in its "small" stage. Bob Fenner>

Cycling/Algae   2/14/06 Good Afternoon, I am a little confused on my cycling process.  I have a 75 gallon saltwater tank that I set up a little over 3 weeks ago with 95 lbs of live rock, 80 lb dry sand and 40 lb of live sand.  I have yet to see an ammonia spike, however I did get a small increase to .50 ppm after about 4 days. My nitrites have remained at 0 and for the last few days I have a nitrate reading of 10-20ppm.  From what I have read and was told at my LFS, I should have a definite jump in the ammonia reading. <Mmm, not always, no> Am I just being to impatient or is it possible the LR cut down on the symptoms of cycling? <Aquarists impatient? Is this possible? Are you breathing? Yes... Heeee! Yes to your speculation, for sure> If ok, I now plan to do a 50% water change and introduce several snails and a few red legged hermits, I also have 2 yellow tail blue damsels in my established 30 gallon tank that I would like to move over. <I would do so> After this initial introduction, how long should I wait until adding other livestock? <A week or more> Ultimately, I want a mixed reef/fish tank. Sorry for so many questions, I do have one more for now.  I have attached a couple of pictures of what I assume is algae that I have not been able to identify on WetWebFotos or any other source. Please advise to what this is and how I should control it, as there is a good amount that is starting to sprout up. Thank you for your wonderful website, Eric. <Can't make out from the small pix, but is almost assuredly a Green/Chlorophyte... and no trouble. Will cycle out and be eaten... Useful. Bob Fenner>

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Marine Aquarium Algae Control

by Robert (Bob) Fenner

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