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FAQs on Marine Algae Identification 31

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: Algae 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 6, Marine 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 18, Marine Algae ID 19, Marine Algae ID 20, Marine Algae ID 21, Marine Algae ID 23, Marine Algae ID 24, Marine Algae ID 25, SW Algae ID 26, SW Algae ID 27, SW Algae ID 28, SW Algae ID 29, SW Algae ID 30, SW Algae ID 32, SW Algae ID 33, SW Algae ID 34, SW 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

Mysterious algae or bacterial film. Please help!         12/4/15
<.... six Megs of pix. What and why do we limit file size?>
Hello! I am currently battling a strange film in my tank.
<Mmm; nah. Do you have a microscope? Can (will) you learn to/use WWM? >
At first, I thought it was cyanobacteria, but the normal methods
<Which are?>
of eliminating that haven't proven to be useful. Reduction of lights, increased flow, more/larger water changes, new/increased GAC and GFO,
<Try PolyFilter or its equivalent>
reducing feeding, and even products like Chemiclean
<A poor idea>
haven't made as much as a dent in it. Then I began to think it might be dinoflagellates. I had an episode with them
before, and I was able to get rid of them by using a multi-pronged approach of blackouts, hydrogen peroxide, a uv sterilizer, and DinoX.
<.... There's an endogenous source of nutrients here... either the rock or substrate is feeding... Try boiling a sample... testing the water>
This stuff, however, also doesn't respond to any of those things, either. It also doesn't have the appearance that the previous dinoflagellates had. It doesn't create streamers of bubbles, and the texture isn't "snotty" like the Dinos were. I am really at a loss here, and I would like to make a positive ID,
<The 'scope; reading on WWM, maybe my book on Algae (see Amazon, Bookfinder....)>
figure out why they've gotten so established in the first place, and come up with a treatment plan. I appreciate any light that you can shed on this matter!
<Have seen a 'zillion times as the saying goes.... the N, P, K source here? hard material/s you've placed.... or much less likely the water, salt mix>
<Read on! Bob Fenner>

Mmm; plus Myrionema?

White Hair Algae - Can't find a way to get rid of it!       9/22/15
I found you’re website off a forum and decided to give you guys a shot at trying to ID this weird algae problem I have.
<Need to look under a 'scope.... see WWM, books I've written re.... My guess (w/ some confidence) is on Cyanobacteria... lack nucleus, plasmids, plasmalemma........ >
I can’t find any resource on how to get rid of this particular type of algae so hopefully you can provide me with some help!
Here is a link to the Algae ID FAQ where someone referred me to.
It looks just like the algae in the “Strange White "Hair" on Rocks” entry.
Here is the link and a few pictures of my tank.
<Ahh! This one looks a bit different than "Jenny's"... again, simple exam will likely show.... BGA>
I just need to know how can I get rid of this! I’ve had this in my tank for more than a year! I’ve tried H202 but it keeps coming back.
Please help.
Thanks for helping!,
<The usual approaches: nutrient deprivation, competition, perhaps predation, increased RedOx/ORP via water changes, Ozone/UV use, chemical filtrants of use.... READ here: http://www.wetwebmedia.com/bluegralgae.htm
"and the linked files above" (quite a jingle, eh?). Bob Fenner>

Algae ID?        9/10/15
Good morning WWM. I have a nice sized colony of macro algae that popped up in my sump. After reviewing Bob's Reef Invertebrate book (one of my personal favorites) I'm leaning towards Dictyota sp. Thoughts?
<Yes; and YEEIKES! What a healthy batch! I'll bet it's sucking up ALL Iodine (ide-ate) supplementation; as well as a good deal of alkaline earth and alkalinity. I'd keep this herd thinned Matt. Bob Fenner>
[image: Inline image 2][image: Inline image 1]
Matt Little

Re: Algae ID?        9/10/15
I'm actually concerned about it making it's way to the display. Probably safer to just remove it entirely right?
<Mmmm; well; I and others find it attractive (not always a pest) and some fishes, esp. Naso tangs come to mind, really enjoy eating this Phaeophyte.
IF you cut it out completely, DO take it to the LFS, offer it on the Net.
Bob Fenner>
Re: Algae ID?        9/10/15

Great, thank you very much Bob! :)
<Thank you for sharing Matt. BobF>

any idea what this is? SW Alg. ID         9/10/15
Thank you for your time! I wonder if you can tell me what this is (I suspect some form of Dinoflagellates) and if it is good or bad. If it is bad, what can I do about it? This is from a SW reef tank that is about 1.5yrs old.
<From the golden color; my guess is on Dinoflagellates... easy to test for w/ commonly available household chemicals.... Or a more resolved pic... with girdling and apical flagella.... See WWM re ID and control. Bob Fenner>
Re: any idea what this is?

Thank you!
<Welcome. BobF>

Algae.... ID       9/1/15
<WHY are you sending us 4 megs of uncropped pix?>
I'm at a loss could you please id this algae, I hope it's not what I think it is.
<.... might not be an algae. HAVE you read on WWM re Identification?
Perhaps Derbesia, Bryopsis.... maybe a Hydrozoan. READ; don't write. Bob Fenner>


Weird algal growth      7/15/15
Hey Bob,
I have an 80 gallon sps tank that's been running for about 6 months. I have this odd turf algae growing on my sand, looks similar to the terrarium moss you can buy for land frogs and chameleons.
<Seen it... see Derbesia; other pest Greens on WWM>

My po4 is 0 (Hannah checker) nitrates zero (salifert and api kit).
<Being absorbed....>

I have never seen this growth before in all my years. Only thing I can think of is the black Hawaiian sand I am using (attract in more lighting)
and am using halides for first time .
I am moving soon, so I can to throw out sand during move and replace with new white sand. But can that be the blame here, even though nutrients are not detectable?
<... the reading>
Lastly, any advice on moving tank to new house (17 miles away) and not. Losing any coral?
<The SOP: http://www.wetwebmedia.com/movingaq.htm
and the linked files above>
Fish I'm confident with, but have heard coral losses are sometimes inevitable.
<Search before you write. B>

Bad encrusting algae      7/17/14
I am not sure if anyone is at this site anymore.
I have some questions concerning some algae that was diagnosed by Bob Fenner as "Peyssonnelia".
I have a similar looking algae as the person on your site does here, http://www.wetwebmedia.com/redalgcompfaqs.htm on 8/22/07
I have considered Dinoflagellates as a possibility, however I am not all together sure.
<This is a mix of a few Divisions of Thallophytes, plus Cyanobacteria...>

Either way here are the things I know about;
It's first sign of existence is the whiting out and dying off of coraline algae. Then you will start noticing dead snails around the tank as they eat the algae and it kills them. Then all other algae in the system dies off as this algae will out-compete even Chaeto. It is dark brown at its base and is very filamentous from its base up. It is hairy yet it encrusts.
The hair on it in one of my systems is easily 1/2 inch long. I have tried killing it with a saltwater/2(HO) mix and that doesn't even kill it. The ONLY way I have found to kill this algae is through lack of light over
many days, an by many I mean almost 14 days. I have attached some pictures.
<Take the long read on WWM re marine algae control period. Bob Fenner>

Re: Bad encrusting algae      7/17/14
I took the long read and came up with nothing that would help with this.
<.... tis the same ole approaches: Nutrient deprivation, competition, predation.... chemical filtrants/improved skimming/higher RedOx....>

I have tried many different techniques and most of them did not work. I am not sure if either Thallophytes or Cyano is correct as neither of these match the description of the algae.
<... have to look at under a 'scope. Easy to see the various parts of this mess thereby>

I have seen quite a few other with the same problem as I have and no one has yet to be able to correctly ID this algae.
<..... my friend. Go back and READ. BobF>

I personally have written about it many different places and no one has been able to ID it yet for me, or help me with getting rid of it. The only thing I can say for sure that kills it, is lack of direct light for a
period of time; at least 2 weeks.

What kind of Algae is this? 7/28/11
I thought it was Bryopsis, but now I'm not sure. It's really starting to take a real hold all over the tank, and is tough to pull out. I had a turbo that would eat it, but it died.
<Mmm, a clue perhaps>
Now all the new Turbos/snails won't touch it..
<And this>
I'm currently dosing Kent tech-m, and at 1700 ppm Mg, but there seems to be no effect on it so far.
<Doesn't open>
<Fragments... does appear to be a Thallophyte (vs. a Moneran/Blue Green... might be BGA mixed in/on), but... perhaps Derbesia... There are a few approaches to control. Read here: http://www.wetwebmedia.com/marine/maintenance/maintindex.htm
scroll down... Bob Fenner>

Re: What kind of Algae is this? 7/30/11
Thanks Bob for the reply,
Here are some better pictures of the menace algae, this was one clump of it. It has a very tight hold on the rocks where it grows. It's also stiff - bristle like, not soft like HA. I'm thinking its a type of Cladophora... your opinion?
<Could be a Cladophora... or Bryopsis... or a Blue Green Algae attached/associated with it. Do you have access to a decent low power microscope? Do see/read on WWM re their use in algae identification. Bob Fenner>

Re Mandarin hlth., was fat lip, now swollen pooter... Alpheid ID, Diatoms 3/11/10
Hey Bob,
Thanks for getting back to me so quickly.
The mandarin seems to be acting completely normal but his issue persists. I wanted to take this time to ask for some guidance on a few issues I'm having. I believe I told you that I recently down-sized from a 75 gallon to a red sea max 34 gallon all in one. I kept about 20 lbs. of live rock from the big tank and added to it about 25 lbs. of new live rock from the LFS. I also saved about 2 cups of sand from the big tank and added 20 lbs of black pacific reef sand to the new setup. I used 2-3 gallons of water from the big tank and added new RO/DI salt water in the new set up. Well the tank has been set up for a month now and I am pulling my hair out dealing with one issue after another. So I hope you can help with a few things because I'm losing faith in my ability to maintain my tank. So here is my current set up:
34 gallon red sea max all in one
20-24 lbs sand
45-50 lbs live rock
I replaced the regular carbon bag from this package with Chemi-pure elite and also added a bag of Seachem Purigen.
I am also running a Aquaripure nitrate filter.
I change 5-7 gallons of water about every two weeks, replace with RO/DI salt water and top off with RO/DI fresh water all bought at the LFS.
Livestock includes:
Mystery wrasse (moved from old set up)
Green mandarin (moved from old set up)
Yellow watchmen goby (added to new set up after 2 weeks)
Scarlet cleaner shrimp (moved from old set up)
pistol shrimp (added to new set up after 2 weeks)
pink tile sea star (added to new set up after 2 days but died after 2-3 weeks)
orange sun coral polyp frag
green starburst coral frag
green Zo frag
Astrea, Nassarius, and turbo snails
water parameters:
ph 8.3
nitrate 0-5ppm
nitrite 0
ammonia 0
calcium 420
<Magnesium? I would test for this...>
Alk 14dkh
I feed the fish frozen Mysis and brine shrimp, and blood worms all soaked in Selcon.
I feed the coral zooplankton or reef chili
I also dose with iodine, purple up, and Seachem liquid buffer as needed.
Alrighty then, I was wondering what species of pistol shrimp I picked up.
<... looks like an Alpheus sp., but I don't see it in my print ref.s or on the Net. There's summat similar on Keyscritters.com, but I don't see this listed elsewhere.>
I have been looking around online and have not found any that look like him. I bought him so that he might pair up with the goby but this doesn't seem like its going to happen
<And can even be dangerous. See today's "Daily FAQs">
and even wondered if he might be responsible for the goby's injury I noticed yesterday.
<Oh yes, could well be>
Secondly, I was hoping you could tell me what caused the sea star to perish.
<See WWM re... there is little hope for this Fromia>
He was in the new tank for nearly three weeks albeit he didn't move around too much and suddenly he has a hole in his disk and what I can only guess were his guts hanging out. And last, I have this reddish brown stuff growing all over the sand bed and the glass and a spot or two on the live rock. Is this Cyanobacteria or what?
<I think "what"... Diatoms likely. Do you have a microscope?>
I can clean off the glass or stir up a spot in the sand and within hours its back. I do water changes and as far as I know keep the water parameters in check so what could be causing this stuff to grow so fast?
<... again... learn to/use WWM:
Well I'm sure you are tired of reading by now so I will post some pics for your viewing pleasure and I hope to hear back from you soon. Thanks again for all that you guys do...
<Wish I could be of more direct, complete help Frank. BobF>

Identification of this Algae... 3/9/10
Hey Guys,
I have a quick question about this algae growth that seemed to just up and appear one day. It started off as a small unnoticeable growth and now as you can see has turned in to a bush! I really like it, I really just want to know what it is. I am hoping you can help me with that?
A few specs about my tank. I know it sounds bad, but I have no idea the params of my tank for the most part. I do water changes on my tank every weekend so, everything seems to remain healthy. I do know the PH is right at 8.2 (Salifert test kit) and I know the salinity is right between 1.024-1.025 (calibrated refractometer). As far as the ALK, CA, Nitrate, Nitrite levels, I am not really sure. The tank is a custom made 75g tank with a built in filter in the back, skimmer, halide lights... It has been established for over 3 years and all is healthy minus the usual reef die off.
Michael Seybert
<Is a nice Rhodophyte of some sort. See here:
and the linked files above, particularly Red Algae ID FAQs. Enjoy this life, Bob Fenner>


Re Identification of this Algae... 3/9/10
Bob, thanks for all your help! I have been scouring the web looking for this species, it almost has orange around the edges and then the middle of the leafs are pink! Anywho, thanks again for all your help!
<Is a beauty Mike. If you could culture it in quantity, this would be worth selling to stores, over the Net. BobF>
Re: Identification of this Algae... 3/9/10
Thanks, I will try and cut a piece off and then grow it on a frag plug?
See what happens!
<Sounds good. B>

Macro Id 3/2/10
Hey guys, I have an algae I'm trying to get an ID for. Looking at your Algae
ID page I think it's either Sargassum or, Ulva, or Caulerpa. I'm hoping it's Ulva, what do you think?
<Mmm, actually... does this stuff "feel soft?"... Am thinking you may have a "green variety" of the Phaeophyte Lobophora variegata here... can grow as this colour and size, shape with conditions that lack sufficient iodine/ide
et al.. See WWM re control. Bob Fenner>
It doesn't grow higher then about 1-2cm and it's about 1cm across. It's growing way too fast and has spread to the sand bed.

Re: Macro Id 3/2/10
I will have to see what it feels like when I get home, but it does look exactly like Udotea orientalis,
<Is a possibility as well. BobF>

Please help serious algae problem -- 02/25/10
Dear WWM,
<Hi Gary>
These things are spread out of control and no LFS can help me ID what it is.
<It's an algae of some kind. Maybe BGA>
It is golden brown jelly-like stuff grows on live rocks and sand bed. Not like any other algae, they are super easy to brush off and floating around then settle down to different places. I have been siphoned they out everyday and they reappear the next day. My nitrate 0 and phosphate 0.05 on Elos testing kits. T-5 lighting ( 9 hrs daylight and 12 hrs actinic ).
<You are feeding this somehow. What are you adding to the tank as well as and apart from food? I have seen this before with people using vodka, or carbohydrate additions for nitrate control>.
Please help.
<Have you looked at all of the many algae control options as well?
http://www.wetwebmedia.com/algaeconMar.htm. There is a source in your tank, of something.... somewhere>
<No problem>

Hairy stuff... 2/23/2010
Hello Bob,
Maybe you can help me with this algae. Can't find it on the internet and
books I have. This time from the Philippines.
Thanks again Bob!
<Can't w/o microscopic examination, possibly physiological testing. Likely
a Cyanobacteria, but could be another Division. BobF>

New Print and eBook on Amazon

Marine Aquarium Algae Control

by Robert (Bob) Fenner

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