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FAQs on Marine Algae Identification 21

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 22, Marine Algae ID 23, Marine Algae ID 24, 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

Unknown algae growth and unknown coral 03/28/2008 Hello Guys and Gals. Thank you once again for all of your help! <<G'Morning, Andrew today>> I have an algae growth that none of my LFS can seem to tell me what it is. It shows up on my sand bed after the lights come on and seems to grow patches within the first couple hours and grows throughout the day. After the lights go out, it seems to diminish a great deal over night. I'm not sure if it's being eaten by my snails and hermits but it is a lot less in the a.m. before the lights come back on. It looks black in the tank on the sand, although I have removed some before and put in a bag to take to my LFS and it sat in the bag for a couple days and turned the water in the bag pink! Then the water turned clear eventually. It has a very fine hair like look when stirred up. <<Yes, its a red hair algae, from what i can see in the picture. There is a good possibility that your snails are keeping this under control. The tufts on the substrate can easily be syphoned out>> I have a 65 gallon tank. 3 1/2 month old, 75 lbs. live rock, 3 circulating powerheads w/ a total 1000 gph circulation. (3) 96 watt lights equaling 50% blue and 50% daylight. Night light is a submergible LED blue strip lights. <<For a reef tank, you may want to up your flow a little, get yourself into the region of 1600gph>> Water parameters are 0 ammonia, 0 nitrites, calcium, 480-500, nitrates are questionable, I get about 20-30, LFS test 0, PH 8.2, salinity 1022-1023. I use Oceans Blend for Calcium, PH, Alkalinity. Had phosphate tested today and they said very minimal. <<Usually with plague algae, they have already absorbed the phosphates from the water, so, a test showing up minimal is common. Have you tested the water before it goes in the tank? If not, give it a test, see what it shows>> I have several small frag corals, mostly soft coral, but some candy cane coral, one Bubble tip anemone and a fair size frog spawn. I also bought a coral today that the LFS told me was a Cotton Candy Coral. <<I would concur on the carnation coral. They are not the easiest to keep, however, with research and understand, you should be fine>> It has extended out at least two inches since I put it in. Now that I am looking online, it looks like a carnation coral! They say that they are difficult to keep. Mine seems very happy in the few hours I have had him but now I am afraid that I won't be able to keep him alive! Included is a pic of it as well. Can you identify this coral? <<As above>> Fish include: 1 Dwarf Coral Beauty 1 Six Line Wrasse 1 Lawnmower Blenny 3 Blue Green Chromis 1 Midas Benny 2 Mated Percula Clowns Inverts: 1 skunk cleaner shrimp 20 Nassarius snails 2 large Mexican Turbo Snails 4 very large stocky Cerith Snails? The ones that burrow under the sand I pulled some of the algae out and put in a bowl for you to take a look at. Please tell me what this is. I have been told may be hair algae, another told me red slime. Another place said they don't know what it is, they have never seen it. Will you please take a look at the pics attached and tell me what YOU think. Also, what kind of coral in the other pic. Thank you for all you do for us! Rachel <<Thank you for the questions, hope this helps. A Nixon>>

Diatom Bloom...  BGA 3/20/08 Hi Crew, <Hello there.> I seek your advice once again. Recently I've experienced what appears to be a diatom/Cyano bloom. <It is what it appears to be.> I have a 90 FOWLR. The recent change I've made was switching from 110W PC's to the Nova Extreme Pro T5 HO (324W). I'd like to start introducing polyps, xenia, etc to start into the reefkeeping life. <Great!> I started seeing this bloom around the time of this lighting switch, but I'm not sure this is the root cause based on the readings, which indicate I should be looking for issues with water parameters and nutrient export. <Exactly, while the lighting has spurred the growth, there are underlying causes that need to be addressed.> I've tested Phosphate (0), Silicate (0), Nitrate (.25), and pH (8.2-8.3 with lights on). I'm using Salifert test kits, so I believe these are reliable numbers. <Yes, these test kits are good. Do be aware these numbers can be deceiving, nitrate and phosphate can be used up as they are produced, allowing BGA growth and yet still yielding low numbers when you test. The proof is in how the tank looks.> I employ an AquaC Urchin skimmer, a 3gal refugium w/ a DSB and Chaetomorpha (which is growing and being trimmed), and 30% water changes every other week. I've attached a few pics of the sand as well as the growth on the rocks. With a diatom/Cyano, I was expecting to see this develop in more stagnant areas, but the pics are where my powerheads are hitting the rocks pretty much head on and is where the growth is thriving. <They idea behind not allowing stagnate areas is to keep detritus in suspension to be exported via your filtration (mechanical/skimmer) or processed by live rock and its inhabitants. The nutrients that cause the outbreak will be spread throughout the tank, causing growth all over. It merely originates from the stagnant areas more than others.> I'm a bit confused on this and I'm wondering if this is really a Cyano/diatom issue or something else. <Nothing else, BGA it is.> You're help would be greatly appreciated, especially if I need to be testing or looking for something else. Thanks again <Welcome, a link with related FAQ's to help you learn how to control this outbreak. Good luck, Scott V.> http://www.wetwebmedia.com/bluegralgae.htm

help indentify a red/brown type algae... no pic, poor English... no reading   03/15/2008 I have this reddish/brown type growth(im sure a algae) here is the description. <Umm, really need a good photo...> It is very fine. It grow approx. 2 inch in height. It looks like i a clump of daisy's(Flowers) You could say it looks similar to a daisy, and moves like a waving hand's coral. It spreads quickly. Every 3 days it will die down where there is no flower on top, looks like dead hair grass algae, but blooms again into a full daisy. I have removed by hand but it breaks apart easily, and of course attaches somewhere else. I have scrubbed it off. and again back in full force. My tank is a reef friendly one. Tangs/crabs/snails/urchins/Seahares none of them won't touch it. It will spread to any of my hard corals that are damaged. But the coral will not die from it. (Not yet anyway) I have looked at many on line pictures or red hair type algae. But nothing looks exactly like it just some similarities. I would like to know if you have any idea what it might be, and if so, any cures? Your help would be greatly appreciated. Thank you. mc <... a pic please. That and/or a long read on WWM re Algal (et al.) Identification: http://wetwebmedia.com/marinvind1.htm Bob Fenner>

Red/brown type algae identification... Hydroids likely 3/19/08 Bob Fenner, thank you for your quick response. Attached are photo's of my mysterious algae as per your request. Again description: It is very fine, reddish/brown in color. Grows like a bad weed. Moves like a wavy hands coral. Has a flower type (Daisy) top on it. <I see this... am glad you sent along such large file sizes... Cropped... maybe Myrionema or such...> Every 3 - 4 days the flower dies down, and what's left looks like red hair type algae, but will rebloom again. If moved by hand it breaks apart easily. Will attach to any coral that is damaged (hard coral) but doesn't seem to kill it yet. Your help of what it is, and what might help get rid of it? Again your help would be greatly appreciated. Thank you. MC <I do believe this is likely a Hydrozoan, not an algae... Need even "closer-up" pix to determine. Read here: http://wetwebmedia.com/hyzoanidfaq.htm and the linked files Bob Fenner>

Brown/green spots on live rock 03/03/2008 Hi, <<Hello Joseph, Andrew this evening>> I want to let you know that I love WWM. You have never steered me wrong. <<Thanks for the kind comments>> The tank in question is a 45 g. tall tank with an 18 g. refugium. Has a deep sand bed (about 4²) a good amount of live rock, 1-250 w. metal halide, with 2 65 w. actinic pc.¹s. <<Sounds good>> I have noticed over the past couple of months, that there are some brownish green spots, usually about 1/8 in in size growing on some of my live rock, and occasionally on the glass. They remove easily, but they keep returning. I haven¹t seen any harm caused by them, but they are kind of unsightly. I would like to know what they are, and how to get rid of them. I¹m including 2 pictures. <<I would need some better pictures really which are in focus. From your description, they just sound like normal algae spots, and you'll just continue to clean as you are. To get a better idea, please re-submit some more photos please>> Thank You, <<Thanks for the questions. A Nixon>>

It's the algae man! RMF

Brown Gray Stuff On Rock -02/27/08 Hey Crew, You're site is such a valuable resource and I appreciate all your seemingly endless assistance. My question is that I am seeing this brownish grayish substance on some of my rock. It is only on a small percentage of the rock I have and seems to be only affecting a certain type of rock. I am not exactly sure what this type of rock is (e.g. Tonga, Fiji, etc), but it is a rather knobby rock. None of my other rock is affected at this time. Most of this substance easily comes off with very little effort using a brush or blowing it off and either settles on the bottom or gets filtered or ends up back on other rock. I do have a certain amount of debris constantly floating throughout the tank due to my Diamond Goby stirring up the live sand, and my water flow keeping it afloat, so it is hard for me to tell if it is growing back, or new stuff is settling on the rock. I initially thought this may be just particles from the sand sticking to this one type of rock, but that seems a bit odd that it only sticks to this one type. <It's not odd at all, some algae prefer some types of surfaces over others to cling to. The rock it's on might be more rough or porous... more conducive to brush or hair algae growth.> Then I thought it might be some sort of hair algae, but after extensive research, I couldn't find any algae that looked like what I am seeing and seems like most hair algae is red or green. I do have what I believe is purple and green Coralline algae growing under this stuff on the rock as it is exposed once I clean off sections. The substance does look very fuzzy, almost like it is statically charged to the rock. My tank is 150 gallons and only up and running for a few months now. <Ah, algae blooms are quite common in new tanks.> My water parameter are pretty good: Salinity is 1.0245, Calcium is around 400, Phosphates are around .03, Magnesium is at 1250, Alkalinity is at 4.1, PH is 8.3, and Nitrates are at around 10. I have attached a picture (probably not the best depiction of how it really looks) and hopefully you can help me identify this issue. Sorry if this is a bit long winded. Please let me know if you need more info. Thanks so much for your time. <Well, it's some type of nuisance brush or hair algae that is collecting debris on its surface. As with any nuisance algae, you'll want to remove as much of it as you can manually whenever you do a water change (even if it means using a tooth brush to scrape it off)... and do more/bigger water changes until it's under control. Check your nutrient levels, try to lower them, etc. Please see here: http://www.wetwebmedia.com/nutrientcontrol.htm> <Best,
Sara M.>

Green Algae ID/Help -02/24/08 Dear Crew, Today, I find myself confronting a nuisance algae uprising, and I've spent about 2 hours skimming WWM and other sites in an effort to determine what I'm up against. This outbreak started this week and seems to be spreading rather quickly to portions of my substrate and the portions of my LR that aren't covered in coralline algae. I do not believe it to be green hair algae, but maybe a green diatom? It has the appearance of grass, or Astroturf. <It's some type of green hair and/or brush algae... possibly growing along with Cyano, diatoms or other bacteria/algae. It might not be just one thing.><<Bingo!>> I have not been able to positively ID it, so I am really hoping someone at WWM can help me figure this out. Two pictures are attached. I feel like I've described my setup to the Crew 100 times, but I think a repeat is essential for this issue: a 110g tank, a wet-dry trickle filter with bio-balls, a Coral Life Super Skimmer, and a 30g refugium. Inside the tank are 4 Maxi-Jet 1200s positioned so that there is turbulent flow. My return pump is a 1,325 gph Little Giant. My lighting is a 760W fixture (two 250W 20,000K HQI's and four 65W true actinics). The actinics are on from 10:30 a.m. until 10:30 p.m., and the HQI's are on from 11:30 a.m. until 9:30 p.m. For all water top-offs and water changes, I use water from my six-stage RO/DI (two of the stages consist of redundant DI canisters)-all filters were recently replaced and my TDS meter reads 0 ppm coming out. I have about 95 lbs of LR in my display, and about 10 lbs of LR in my fuge (5" DSB and large tuft of Chaeto). The Chaeto tuft in my fuge had gotten quite large, so I pruned it 2 days ago by about 1/3 by pulling clumps off the main body rather than cutting (for which my LFS gave me $5 store credit today!!) and I also stretched it out a bit so it wasn't as compacted. The lights on my fuge are on a reverse daylight cycle opposite my display lights. Now for the important stuff: my water parameters (as of last night) are 0 for ammonia, nitrite, nitrate and silicate; alkalinity is 3.5 mEq/L; specific gravity is 1.025; pH is 8.3 during the day and 8.1 at night; temp is 80.1*F; calcium is 400; and (and maybe a big "and"?) phosphate is 0.03 ppm (confirmed on both a Salifert kit and a SeaChem kit). I checked the phosphate in my pre-mixed salt water, and it is likewise 0.03. I then tested the fresh water coming out of my RO/DI unit, and phosphate was 0. So, contrary to the manufacturer's claim, it would appear that my Instant Ocean salt mix has some phosphate (I know this is a very reputable, old brand. I have read all the literature on WWM and the web about salt mixes, and it is clear that there is no consensus on the "best" mix. It also seems that most people recommend Instant Ocean). <Very true, there is no consensus on this. Instant Ocean is an old stand by and certainly many accomplished marine aquarists have used it for years. However, it has been known to be inconsistent and at times imperfect. Have you seen this? http://www.aquariumwatertesting.com/AWT_Salt_Analysis_0208.pdf> The tank has been up and running for 11 months. I feed my fish once or twice a day--I rotate Formula One flake, live black worms, Spirulina flake, dried seaweed, Hikari frozen Mysis shrimp (thawed and rinsed), Hikari frozen blood worms (thawed and rinsed), and live littleneck clams. I target feed my tree corals twice per week with Cyclop-Eeze, and I feed my Open Brain coral small silverside pieces once per week. I change 10% of my water every Sunday. The only supplement I use is ESV B-Ionic 2-part calcium buffer, as needed with testing. As stated above, this outbreak came on quite quickly. It first appeared on the substrate in a corner of my tank (where there is good flow!) and now it's spreading to my LR and the other end of the tank. For the most part, it is not spreading to any surface that receives a lot of light--rather, it appears mostly in shaded areas. I can't figure out why this would happen after 11 months. <It happens. Most aquarists have this false idea that the tank is "done" cycling after a month or two. The truth is that marine tanks often don't become "stable" until after a year or so (and that's assuming there are no interfering major changes in that year). And even in older tanks there can be periodic algal blooms that seem "unexplained." It could also be the inconsistencies in your salt mix. It's hard to say for sure.> I noticed that it's hit a rock on which I have several Rhodactis and it is growing between some of the polyps, so immediate action is required. When I do my water change tonight, I intend to use a toothbrush attached to my syphon hose to try to get as much out as possible. <Good idea.> I'm wondering if the former size of my Chaeto has something to do with this, i.e., that it had outgrown the fuge and wasn't growing/absorbing phosphates? <That's possible.> Any thoughts you have will make me happy. <Sorry I can't give you a more definitive answer, but such is the nature of these things sometimes. Sometimes it just doesn't take much to throw things out of balance (out of your favor). The problem with nutrient tests is that the nutrients could be registering zero because the algae is using them up. Given what you've told me about your Chaeto and salt mix test, I think you might have a phosphate problem. Do you have a media reactor? If so, you might consider using a phosphate sponge media in it for awhile. And of course, doing bigger water changes for awhile might help (unless of course your salt mix is the source of the problem-- then you might want to consider switching brands).> Thank you for your time/help. Andy <Good luck, Sara M.>

Re: Green Algae ID/Help Thanks for your help Sara. Do you have a suggestion for a good salt mix alternative (i.e., which brand would you buy if you were in my shoes)? <Oh, tough question... I use Reef Crystals because it seems like one of the better overall salts for reef tanks and it's available just about everywhere and usually isn't too terribly expensive. But do take a look at the chemical analysis data I linked you to. If nothing else, it is pretty interesting. > Andy <Best, Sara M.>

Green Algae ID/Help -02/24/08 Sara, First, thanks again. You always offer great information and are a lot of help. <Thanks, we try :) > I have read that salt summary before--very interesting/informative. I was thinking that maybe the ESV activated carbon that I am running in my sump could be leaching PO4? <It's possible.> I read an article by Steven Pro that tested a bunch of carbon brands, and ESV was one of the worst. Interestingly, I did swap out my carbon this week, but I don't think this is it as I've been using this brand for a while. Plus, since my PO4 is only 0.03 ppm (which really isn't all that bad) and since my display water matches exactly my pre-mixed salt water, my guess is that the problem is a bad batch of salt (I've always used Instant Ocean). <Looking at the data in that report, this certainly seems possible too.> I'm kind of surprised that a PO4 level of 0.03 ppm could spark this sort of problem--I guess I'm assuming correct testing instructions, which say what is and isn't a good PO4 level. Of course, who knows what isn't being detected because it's being immediately absorbed by my Chaeto! <Ah yes, as I mentioned earlier, testing for nutrients can be misleading when you have an algae breakout (or are using macro for nutrient export). The nutrients get used up by the algae before they're detected.> I just ordered some Reef Crystals (was almost out of salt anyway), PhosBan and some Marineland Black Diamond carbon (I've read that it's a pretty good brand). I don't have a Phos reactor but was thinking of running a bag in my sump and floating a bag in my pre-mix vat (wouldn't you know that I mixed my saltwater yesterday??!! Hate to throw out 30g of saltwater). <This sounds like a good plan. Sorry you have to waste the water, but better safe than sorry.> Andy <Good luck, Sara M,>

Green Algae ID/Help -02/25/08 Dear Sara/Bob, I see from RMF's commentary to my post on WWM that he thinks this is a Cyano bloom. Do I interpret his comment correctly? Andy <Is at least partly this highly likely. B>

Re: Green Algae ID/Help   2/27/08 Dear Sara/Bob, I see from RMF's commentary to my post on WWM that he thinks this is a Cyano bloom. Do I interpret his comment correctly? <<Indeed, the green stuff on the white gravel looked like Cyano. But it looks like you have other nuisance algae also (the turf-like one on the rocks for instance). But honestly, it doesn't really matter. Nuisance algae is nuisance algae and they're all more or less caused/cured by the same problems/solutions. -Sara M.>> Andy
<Is at least partly this highly likely. B>

May just look green. RMF.

Red unidentified plant type thing   2/8/08 Hey there Wet Web! This is about my mother's tank. Recently, I believe within the last three months, this red fern type thing grew. <Neat!> We didn't worry about it at first because since live rock can grow things, it didn't seem like a big deal; as there have been many strange things growing in there. However, I was looking at it tonight and I see little worm type things wiggling around inside it( I couldn't get a picture of them but they are the same color red as the thing). <Are a separate item> She is concerned that it may be bad. Some of her fish and snails have died rather unexpectedly recently. She does regular water changes, and tests ( everything has been normal as far as levels). The worm type things are similar to something we found months and months ago under a rock. But this fern-ish thing, we can't find anywhere to identify. We would be eternally grateful if you guys could help us out, and let us know if it might be detrimental to the tank. Thank you guys( and ladies), N. Alps <This is most likely a Rhodophyte (Red Algae), but could be a Cyanophyte... the worms are just using it as habitat. If concerned, I would vigorously vacuum all out... scrub the rock with the siphon end... Bob Fenner>

New Print and eBook on Amazon

Marine Aquarium Algae Control

by Robert (Bob) Fenner

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