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FAQs on Marine Algae Identification 39

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 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 31, SW Algae ID 32, SW Algae ID 33, SW Algae ID 34, SW Algae ID 35SW Algae ID 36SW Algae ID 37SW Algae ID 38& 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,


20 gal Nano... ID     5/5/20
Hello, its been quite a long time since I've emailed for help.
I have a 20 gallon long nano reef tank that has been setup for about year. Currently
all I have in it is some green star polyps, 2 Juvenile Snowflake clowns and a sharknose goby.
Everything was fine until about a month and half ago, I seen this little white, hard, almost calcified
branching (sponge?...Please see photos)
<Maybe; or... polychaete worms, algae, or...?>
in my overflow box. Within in a week I started seeing it on the rocks and the walls of my tank and in my sump. Over the past few weeks, its multiplying like crazy.
It was all over my pumps, reactor, heater, and the walls of my sump too. I tore my sump apart and scraped it off the walls and the equipment, and did a 10 gallon water change.
Also cleaned my overflow box as best as I could. Its still on 2 of the largest rocks in my tank. In my 18
years keeping reef tanks, I've never seen this stuff before. Is it a sponge?
<It might be. Need a closer, better resolved pic>
and how do I get rid of it. Its extremely invasive.
<Either keep removing physically (no fun), try to introduce a competitor, predator...>
Thanks in advance for your help.. and I hope you are staying safe during this pandemic.
<Thank you, Bob Fenner>

Unidentified something?     10/20/19
Hello Bob,
Attached is a better picture that you asked for to see if you can identify what is circled. These are all through my 20 gal. marine tank.
<Likely a red algae species; see here:
and the linked files above. Bob Fenner>

Algae stages, SW      8/19/19
Hello Crew!
<Hey Danilo>
First of all I want to thank all of you, taking the time to answer questions—albeit probably some are very redundant I imagine LOL. Truly you all have patience!
<We do try>
I have a 28 gallon JBJ and sometimes I see what appears to be a little bubble algae or a tubes of green bubble algae but it transforms into hair algae when it matures.
Am I imagining things, or is this how some green algae develop and that seemingly bubble algae is in fact just hair algae in an early stage?
<Could be that the bubble algae is popping/decomposing, leaving thread like processes behind, but I do think what you're experiencing is "succession", the one type/species (of green bubble algae) being overgrown by a different, filamentous species. Does happen. Aquatic environments can be very vivacious>
I appreciate your insight!
<Do see/read on WWM re all types of algal control if interested. Cheers, Bob Fenner>

Coralline Algae, Cyano, or ???     8/3/19
Hi Bob -
I am stumped trying to figure out exactly what's growing on my glass and rocks in my 265 gallon FOWLR tank. I've attached a few pictures. It doesn't come off very easily at all. Frankly, to get it off the glass you have to use a scraper with some force, then to get it off the rocks, good luck as a tooth brush will very slightly thin it out, but if I really wanted it off, more likely it would take a steel brush with some force to get it off the rocks. Further, when I scrap it with force off the glass it comes off as a dust, not in sheets.
Thus, based upon this hard consistency my gut tells me it's Coralline Algae, yet I am used to Coralline algae being pink or light purple, not red in color. It's a dark, burgundy red, similar in color to cyanobacteria, but I definitely can't siphon it out like you can with cyanobacteria. Should I be concerned?
Thank you,
<Hey John. Coralline (encrusting Reds, Rhodophytes) are very different to the touch than Blue Green "algae"/Cyano... The latter are slimy; and of many different colors. Reds are not slimy, but hard, crusty... From your description and photos this appears to be BGA...
Yes to being concerned... conditions that allow, encourage BGA are deleterious to most all other life forms as are some of the metabolites of Cyanobacteria.
Please read here re the several approaches to control: http://www.wetwebmedia.com/bluegralgae.htm
and the linked BGA Control FAQs above. Bob Fenner>

Re: Coralline Algae, Cyano, or ???     8/4/19
Ugh. Terrific article. Thanks Bob!
<Cheers John! BGA is defeat-able, avoidable... Like steering a large ship w/ a small rudder; takes a while, but... slow and steady is the route to go. BobF>

Algae ID     6/25/19
Good morning from Thailand,
<Hi Dirk from Thailand!>
I have attached some pictures of some algae I am getting very frustrated in and seem to be taking over this aquarium for the longest time now. Aquarium has no fish inside and only houses 2 seahorses which are only fed live brine shrimp and copepods. No food added ever to this tank for about 1year++Water tests show 0 Nitrates and 0 Phosphates. Top off is done with RO/DI water, I dont have silicate test kit so not sure if that's available. Have been putting phosphate remover in the aquarium added extra bacteria to try and out compete this algae but .....Shut of the lights for several days which seem to effect them slightly to just return in force as soon as light goes on. Tank has also a large toadstool, 2 elegances and some red ear and branch sponges.
<What are the dimensions of your system, water volume?... also, what type of filtration do you have, do you run a protein skimmer, ozonizer? These last two help by limiting nutrient availability which is used by BGA (blue-green algae) to reproduce.>
We have tried everything even at one point removing all stone cleaning them removing daily manually, phosphate remover......but this thing keep going and going.....added blue legged hermits, Turbos, Algae crabs, had a Seahare in it even for a while....
<Do you have a sump?... a DSB with macro algae in a reverse light cycle really helps on getting rid of this nuisance algae.>
Cant really seem to find any positive ID on the net either maybe you guys can help?
<This appears to be BGA (blue-green algae).>
thank you for any advice possible...
<You’re most welcome. Wil.>

Re: Algae ID     6/25/19
Hi Mister Will,
Blue green algae are they not to be Cyano bacteria rather then algae?
<Yes, that is how it is called and it is either blue, green, red or brown.>
Not sure if you noticed what I send on the pictures but what I am referring to what is taking over my tank is not a bacteria but rather a green looking plant....see again attached picture with marked what I referring to.
< Yep, it is BGA.>
As for the system yes a skimmer is present in the system though no extra space for a refugium is available.
<I suggest you to perform a large 30% water change, followed by weekly 10% until the problem is solved, please see the following link and related ones. http://www.wetwebmedia.com/cyanocontrolfaqs.htm . Wil.>

ID        5/14/19
Hi Crew!
Been a while since I’ve messaged you all, hope all is well. I was wondering if you could ID this red growth all over the corners in this tank?
<What a beautiful Rhodophyte. Perhaps a member of the genus Fauchea>
I volunteer for an aquarium and the curator says it’s a type of macro algae. Thank you in advance, I appreciate your time!
Dani ��
<Thank you for sharing. Bob Fenner>

Please ID this      2/9/19
These mushroom looking growths came on the live rock after a neglected time to as far as lighting was concerned. I purchased the rocks abt 13yrs ago...they came out when I just had a FOWLR saltwater tank...right now they are in a new tank with an AI Prime HD lighting...wondering what they are and their ideal lighting requirements. Thxs for your time
<This, these appear to be some sort of Rhodophyte, red algae... are they brittle to the touch?
Do review what we have re such on WWM:
and the linked files above. Bob Fenner>

Need ID      1/24/19
Hi Crew,
Can I get an ID on this coral?
<? Coral... this looks to be a bit of Colpomenia; a Brown algae. Bob Fenner>

Re: Need ID      1/24/19
Thanks Bob
<Welcome Beta>

Red algae?    12/4/18
Hi crew
<Hi Cathy>
Could you please help with an ID on this red algae it is a solid firm jelly mass that showed up in my sump looks harmless just want to make sure. It floats hasn't attached to anything doesn't seem to have branches at this stage, the side on my hand is smooth the side you can see has little lumps.
It's growing slowly only noticed it a month ago when I moved things around and it floated out.
<Looks like Botryocladia sp. Please read this link: http://www.wetwebmedia.com/redalgidf4.htm>
Thank you
Cathy Napoli
<Glad to help. Wil>

Re: Red algae ?     12/5/18
Thanks Wil so grateful for this site.
Thank you
<Welcome Cathy!>
Cathy Napoli

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.>

Red tipped macro algae ID     9/18/18
Ah sorry, I was using an old email thread—thought it was still attached, here you go!
<Looks like some type of Rhodophyta algae>

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>

Nuisance algae......or is it?!     1/11/18
Hi guys, been using WWM for at least 15 years now and always recommend it to new and experienced Aquarist alike.
Now I need some help though please. My 200gallon reef tank is about 18months old and has always had good pH (8.1 to 8.2), temp (26oC), alkalinity (8-10dKH), calcium (400-450ppm), magnesium, etc etc. My nitrates are always virtually undetectable but exist and my phosphates the same but show 0 on my Salifert test kit. I have a Tomini tang, purple tank,
magnificent Foxface, 2 Percula and 1 Chromis. Also several conch, sand sifting stars, snails, etc although no hermits.
I have different macro algae in my sump
<On an RDP light schedule I hope/trust>
and skim a nice cup of brown off every few days (Skimz mini 1000 skimmer).
I have a hell of a lot of turnover within the tank (2 x Maxspect gyres xf250 on lunar tidal cycle & 3 x all pond solutions synced powerheads putting out around 8000lph each on full. I also use an Ecotech L1 as my return pump set to about 50%). I have 2 main 180w maxspect r420rs on my DT and 1 x 60w r420r on my sump on alternate settings.
<Sounds good>
About 5 weeks ago I added some reeflowers white sand stuff and boom (!!!) I get the outbreak that can be seen in the attached picture. Do you think this is diatoms, Cyano or dinos??
<Most likely BGA, does it feel slimy? Have a look under a scope... Cyano lacks nuceli...>
If I turn over my sand then the brown
<Brown? This looks red in the pix. Might be something else. Again, READ on WWM re ID... iodine test, simple viewing under a moderate power microscope... will reveal simply>

appears back within hours and is now starting to spread on to my rock work.
<... can't tell w/o high resolution. The rock looks like a nice encrusting red in the photo>

I need to know what it is to try to combat it. I have performed all the general mitigation measures such as reduce feeding, increase flow, reduce photoperiod, increase amount of macroalgae but it doesn't appear to be shifting. Any identification and/or advise you could give would be very gratefully received.
<Uhh, read here: http://www.wetwebmedia.com/algaeconMar.htm
and the linked FAQs files above>
I have also put a pic on of what my sandbed looked like before this outbreak!
<This looks like Cyano...>
Yours patiently, Martin Gorton
<Cheers. Do please write back w/ your further observations, efforts/effects. Bob Fenner>

Nuisance Algae (possibly sponge?) in saltwater tank     10/11/17
Hello. I have this weird yellow/tan algae (or sponge?) growing in my 10 gallon work saltwater tank. I have no fish in the tank. Here are some photos and a video of the junk in question. I don't believe it's a sponge,
simply because of how it grows. It looks nothing like the sponge in my big reef tank at home. It covers the glass pretty quickly so I have to clean the glass every few days. It seems to be photosynthetic. Do you have any idea what this is?
<Could be algal, but my guess is on a sponge here. You might consider cutting a piece off and looking under a 'scope... for choanocytes likely. Bob Fenner>
<https://drive.google.com/file/d/0BzPR3-najOZBSkxUM25aTXVoX3M/view?usp=drive_web> ​​

Re: Nuisance Algae (possibly sponge?) in saltwater tank     10/12/17
<PLEASE: No files more than a few hundred Kbytes... >
A thin layer will cover the glass just within a few days if I leave the lights on. Here are two additional photos I took. I will check it under a microscope and see what I come up with.
<Do send along reduced size, highly resolved pic/x if you can>
Thanks for your help!
<Thank you for sharing. BobF>
Re: Nuisance Algae (possibly sponge?) in saltwater tank     10/12/17

I will send the microscope images over when I get them. I was sending full size photos so they were large. I will reduce next time.
<Ahh; I thank you Justin. B>

Macro ID       7/19/17
Asking for a friend. Need ID on invasive macro, it is over running and killing corals. No idea origin of live rock. Thanks
<... what is this?! Green something w/... blue dots!? Do you have a means of sampling, making some microscope pix and sending them along? Bizarre.
Bob Fenner>

Re: Macro ID  7/27/17
I've requested a close up but it's not forthcoming, he says the blue is from his camera. It's killing off his corals rapidly. Here's an out of water pic.
<... can't discern even the Division (plant taxonomy, akin to Phylum in zoological tax.) w/o seeing the cellular structure microscopically... Have you read on WWM re algal control period? Do so. Bob Fenner>

Help ID what is growing on our rocks.     7/11/17
Resize and re-send... your pix are two orders of mag. too big (39 megs...)
Help ID what is growing on our rocks. Without Video

I’m in need of some help identifying what is on our rock. I’m attaching pix to help.
Sg 1.025
KH 8.3
Ca 412
Nitrate/Ammonia 0.00
Age 5months.
Temp 77.5 to 78.5
Neptune Apex controller used to control and monitor various things.
We were using Kent Marine Salt. BRS 2 part dosing ~1ml/gal day (Seems a bit high for a tank with not much in it).
Reef Octopus skimmer,
Reef Octopus vario-s 6 return pump.
2 MP40’s
1 of the original Gyre 150s
We have been working to get our levels to stabilize, we are there.
This stuff seems to have been there a while, didn’t start to take off until recently. The pix/vid are before pix. We vacuumed as much as we could 2 weeks ago, last week our A/C went out. Lights out on the tank, we put a portable A/C in the fish room and kept the temp about where it normally is. I climbed briefly to 81, but stabilized at 78.7. Right before the A/C went out we switch salts to the AquaVitro Salinity salt, about a 100g change.
After the A/C outage most of it went away. I think it is coming back, looks like a light film on the rock that is starting to bubble.
I was already thinking of changing salts, when our LFS told us he had never seen what we have before and did not think it was organic that is what pushed me over the edge.
William & Pegine
<Mmm; I'd sample a small bit and look under a microscope... You can read re on WWM including cheap 'scopes. This looks like a pest Dinoflagellate to me... Sometimes REALLY hard to get rid of; AND not palatable (to fishes, most invertebrates that eat macroalgae growths); SOME are VERY toxic. Friend Sanjay Joshi is having such an issue, and we're currently chatting up on Facebook... Jules (Sprung) gave this useful link: "A Quick reference Guide? Check out this interesting new site online: http://www.algaeid.com/about/ ". Denying nutrient, improving ORP... are the steps to go toward here. Bob Fenner>

Salt tank, growth.... ID        6/11/17
What the back is this on my glass?
<Looks to be mostly coralline (encrusting Red) algae... with some green, blue-green algae on the side.
Bob Fenner>


Re: Salt tank       6/11/17
Yeah! Just inherited a 29 and loving it. Thank you.
<Ah, good. Cheers. BobF>

Need help for Species Identification        4/26/17
Hi Bob! You've been a great help to me during my coral identification. I wonder if I could ask again for help to identify this marine alga?
My initial identification is Colpomenia sp. but I'm not quite sure.
Thanks a lot!
<Could be... where is this algae from? Do you have any microscope pix? Bob Fenner>

Re: Need help for Species Identification        4/26/17
It's from Pagudpud, Ilocos Norte, Philippines
<Could be... does it feel somewhat hard to the touch? Though hollow? BobF>
Re: Need help for Species Identification        4/26/17

Yes it's hard and hollow.
<Ahh; do see/use AlgaeBase per the genus to examine possible species. Bob Fenner>
Re: Need help for Species Identification        4/26/17

I got no microscopic pictures and all I've got is this pressed specimen.
<Can't tell any more from this. B>
Re: Need help for Species Identification        4/26/17

I've looked through it but there was nothing similar to the specimen.
<Ahh; Bob F>

Re: Need help for Species Identification... Phaeophyte ID       4/27/17
Oh I did and I identified it as Leptoplyngbya.
<Ahh, A Cyano...? Not. Bob Fenner>

Red algae?      3/28/17
This appeared in my tank like 9 months ago The tank has been up up and running for 15+ years. Nothing has been added coal wise in 4+ years. No live rock has been added in like 10 years.
Just started grow out of the blue. And it grows very fast! Already cut some out. Looks cool but is it bad or good?
<Are there signs of poisoning... of your other livestock? This looks like a Rhodophyte, but might well be a BGA... esp. strange that your tangs aren't consuming it. Is it (very) slimy? Do you have a simple microscope that you can look at part of it under? I'd like to see pix if the 'scope has a USB conn. I would remove it as it grows... Look to the usual: nutrient limitation, competition, DSB/Refugium on RDP... perhaps the assiduous use of chemical filtrants (Chemipure, PolyFilter) monthly to limit. Bob Fenner>
Todd Washowich
A microscope? Dude I haven't used one since 6th grade. 😂. Is not slimy. And nothing has died in a long time.
My filters are just a butt load of live rock in my sump in the basement.
A protein skimmer as well. We do not do any additives at all and do 70 gal water changes I had a run of Cyanobacteria a month ago. Only thing added was what a slime X or what ever.
But this was growing long before. I may try to find a microscope though. But of course I would not know why to look at.
<Am back to the Reds then... an unpalatable one (there are many). And the suggestion to remove on a weekly basis; cut off and siphon out; address the HPO4.>

Seaweeds ID       3/4/17
<20 plus megs... overloaded our email server. Sorry to all who got bumped>
To whom it may concern:
Good day. I am Maria Quiao from the Philippines. I am just hoping if you can help me indentify the seaweed sample I collected in the intertidal zone of the tropical coast in my country.
<Is a brown/Phaeophyte; Fucales...>
It is brown seaweed in the genus of Sargassum but cant be sure to the species level. Can it be Sargassum ilicifolium or Sargassum polyphyllm or Sargassum polycystum or Sargassum aquifolium... I am hoping that you can help me. Thank you.
<Appears to be a Sargassum species... all I can tell from your images. Bob Fenner>

Algae Id     3/3/17
Hello and thanks for a wonderful site!
<We're here for you Curt>
I'm trying to get a general idea of what I'm fighting in my 90g reef tank that's a little over a year old. The attached picture shows a small sample of the brown slimy film that's on my rock and sand bed.
<Seen, experienced stuff like this ever since when. >
It doesn't seem to kill and/or attach to any of the SPS or LPS corals in the tank and is easily removed with a toothbrush but will grow back within in a few days. The only partial remedy I've found is when I soak each rock in a mix of 50/50 salt water to hydrogen peroxide for about 15 min.s. After the soak, the rock looks great for about a month or two before the growth comes back.
<Yes; conditions still favor it>

Recent tests results show 0 nitrates and phosphates,
<Being absorbed....>

Calcium=445, Alk-8.1, Mag-1440. I'm leaning towards a type of Cyano but really unsure and can't find any positive Id's on the net. Any idea what I'm up against?
<From a macro pic only can guess; this could be dinoflagellates, Cyano, a mix... need to sample and look under a low power (a few hundred time) 'scope. Send pix if you can. The usual mix of possible measures can be gone over here to combat: http://www.wetwebmedia.com/algaeconMar.htm
Am a big fan of a maximum, mixed approach: Competition, nutrient deprivation; enhanced DO and ORP... Do you have a tied in sump? An RDP refugium w/ a DEEP and large as practical DSB is a very good idea. Bob Fenner>

Identification - 2/11/2017
Your image files are too big... have been deleted. Re-size and re-send. B
re: Identification

Sorry, try these
<Hi, Chris
Jordan with you today. You have a beautiful macro-algae in the genus Laurencia, most likely L. iridescens. I'd be willing to bet you're live rock was in the Caribbean at some point and picked it up. It's a non-invasive species that I would be pleased to find in my tank.>


re: Identification 2/10/17 - 2/11/2017
Thank you Jordan!!
Good to hear. Will the Nudibranch (that photo bombed my pics, and also a hitchhiker lol) be an issue with it?
<Haha, didn't see that guy earlier. Looks to be an Elysia crispata, a beneficial herbivore from the Caribbean. You hit the hitch-hiker jackpot with this rock! It shouldn't bother the Laurencia as it prefers filamentous Chlorophyta including the dreaded Bryopsis>

... Marine algae... reading         5/9/16
Hi crew-
I am kerflummoxed...
I have been reef-keeping for over 10 years and am experiencing an outbreak of something in my established tank. I have NO idea what it is, and haven't been able to find anything similar anywhere online or speaking w local established experts. Is VERY fast growing. I did a full manual removal of this stuff a month ago, and it is back with a vengeance. It is very thick and firm/gelatinous. It looks a bit like Cyano on the surface, but the meat of it is white/translucent, as you can see in the last picture.
<Mmm; I really wish you; heck, everyone, had a small microscope... w/ a USB hook up. Easy to tell algae to the Division (Phylum in zool. tax.) thus... impossible w/ the naked eye>
My water param.s are decent, my flow is very high.
<.... what data is this?>

What in the world is this stuff and how can I get rid of it?
<.... how much reading do you want to do? Start here:
and the linked files above>
Do I need to do a full tear down and start over? I'm at that point - super frustrated.
On the advice of a local store, I added a diadema urchin yesterday - total mistake.
<... of no use here>
It was dead by morning, which made me quite sad. I am guessing that this stuff is toxic.
This fish in this system are doing fine, btw.
I greatly appreciate any advice you can offer.
many thanks-
Jim Gray
<Educate yourself. Read on! Bob Fenner>

Chaos in my tank. Mysterious Anthias losses       4/22/16
Hi. I have a 90 gallon reef tank with a 30 gallon sump and roughly 110lbs of live rock plus more in the sump. Livestock includes two young black clarkii clownfish approximately 1 inch each, A small 2.5 inch Bluejaw trigger, a lawnmower blenny, a diamond goby, misc. snails, three emerald crabs, and a sea hare.
<What species is this Aplysiid? Most are NOT compatible for hobbyist, reef use. See WWM
A mixture of corals like birds nest, frogspawns, Zoanthids, and a few Acans.
<And READING re Zoanthids>

I was at the LFS and told the woman that works there that I don't have any swimmers in my tank. The Clarkiis never go far from the rock they are hosting. The Bluejaw trigger just chases his reflection in the glass on the left side of the tank all day. The diamond goby moves sand like he's building a skyscraper all day long. The lawnmower blenny picks at my glass or just sits on a rock and looks at me. None of my fish swim in the water. When people see my tank they think it's just corals and rarely see any fish unless they stare at it for a while. So I asked her for suggestions on a swimmer, someone who will be active in the tank. I told her I'm not a fan of tangs. She suggested a foxface Rabbitfish and a few Anthias. I usually take her word for things. (She's one of the most respected LFS owners in the area). So I picked up 4 square Anthias (1male and 3 females) and a foxface. I realized the next day while doing research that they require a larger tank in general, or at least the square Anthias do. I drip acclimated the fish (separately)
<I would definitely have run all through a SOP dip/bath; as gone over on WWM... to exclude external parasites>
and quarantined them for about a week. After the week was up a I drip acclimated them to the display tank. I put them in with the lights out. The foxface appeared to take the transition quite well. The four square Anthias were another story. Three of them did great and one just laid down in the bottom of the tank. I figured she just needed some time. This is how the tank stayed for the next two weeks. Everybody doing great except for the female Anthias was always laying in the bottom of the tank. She had no sign of illness and I had read that it can take them a while to feel comfortable so I gave her time since she looked healthy. I had an automatic feeder with NLS pellets feeding three times a day and I gave frozen Mysis shrimp every night. Everybody was getting food. The female laying in the bottom would never even try to get up and get food. I came home one day and the Anthias were nowhere to be found, any of them. The foxface was black and in the corner. I put some food in the tank to see if anyone would come out and everyone came out to eat except the Anthias. The foxface even turned back to yellow and came out to eat. I started looking through the tank and found the male square Anthias dead under a rock, then found two other Anthias laying in the bottom alive but seemed scared. The fourth one I have yet to find. I'm thinking the cleanup crew already disposed of it. Not knowing what's going on, I didn't know what to do next. The next day another Anthias died, and then... the last Anthias died. I spoke with the lady at the LFS and she said I have a bully.
I know Clarkii clownfish can be super aggressive but these guys are really young and small. The blue jaw has never messed with anyone and is scared of just about everything. She said it sounds unethical but by <buy> some cheap peaceful fish and see who is doing the bullying. I thought it was a bad idea but didn't know what else to do. So I bought five Blue Chromis.
<Not a hardy species>
I put them in two days ago. Two died the first night the other three died the second night. Then the foxface swam around the corner covered in what looks like ich. The foxface is now in the hospital tank in hypo salinity with ParaGuard and the heater set to 80°F. Everyone else is doing fine. All my water parameters are good Ammonia 0, Nitrite 0, Nitrate <10, PH 8.2. I'm thinking someone is being aggressive but I was keeping a close eye on the tank and never saw anyone not getting along. Clearly I have an issue. Any suggestions as to who my bully is or what step I should take next. Other than the Foxface, no one has shown any signs of illness and this foxface is the first time I've ever had ich in my tank and it's been running for 2 years with no issues. I quarantine everything before putting it in my tank and I reef dip my corals. This is the first time I've ever really had an issue and it's frustrating. Please help.
Thank you,
<My guesses, probabilities lie w/ the Anthias being weak to start with, further weakened by the quarantine process (this species is NOT "open water", but more inclined to hide); AND poisoning via the Aplysiid and/or Zoas. Please do the suggested searching, reading ON WWM; and write back w/ your further input. Bob Fenner>

Re: Chaos in my tank       4/23/16
The Sea Hare appears to be a Aplysia dactylomela after reviewing WWM article on sea hare identification. I Have someone lined up to take the sea hare off my hands.
<Good; I would>

I've been planning on rehoming it for a while. I don’t have much algae for it to thrive on and he seems to be growing tired of eating New life spectrum algae pellets. I've never seen him release ink in the tank and nobody messes with it. Is this type of sea hare a bad thing to have in my tank?
Is it toxic in a manner other than releasing ink?
<There is some speculation. A fave ref.: http://www.seaslugforum.net/showall/seahares

I'd really feel bad if I rehomed him and he causes issues in someone else's tank.
The Zoanthids have never been an issue before. They were the first frags I ever purchased a long time ago. I'm just curious if they need to be removed. the Foxface Rabbitfish (Siganus vulpinus) That is currently in the quarantine tank. Should I just treat it for ich for a few weeks and try to reintroduce it to the display tank?
<Please read what is archived on WWM re Acanthuroids and Crypt>
How can I be sure it is in fact Ich. It has misc. white spots that look like little pimples scattered throughout both sides of his body and a few on its fins. I know this fish changes colors when stressed but can some of that color change include white pimples, roughly a dozen or more on each side?
I also recently after the death of the Anthias had to remove some rocks from my reef tank. They had an unidentifiable (to me and the LFS owner)algae growing on them. It was solid green and not loose or soft by any means of the words. It appeared to be a green staining that appeared overnight and got darker and darker every day. The woman at the LFS said she had seen that one other time and it was due to the rocks leeching copper.
<?! VERY unusual>
I removed them immediately and replaced it with a piece of dry rock I picked up at a different LFS. I took my water the next day to have a copper test performed and it had a very minimal amount of copper in the water, Just barely any color to the reading at all and nothing I should be super concerned about but I'm running CupriSorb anyway. Could any of these recent events be caused by this mystery algae?
<Possibly. There are definitely many toxins associated w/ a great deal of algal species>

Or the copper?
<.... would have to be a "chain reaction" here... a cascade effect. "Some" copper is essential... as a micronutrient...>
The algae was very, very green, no hair or filament nature to it, it wasn't removable. I scrubbed these rocks with a stiff tooth brush for about thirty minutes to no avail. The sun is the only thing killing it. It didn't look like any type of coralline I've ever seen and it only grew on three rocks I picked up from a local reefer who had had them out of a tank and dry for close to three years. The algae literally showed up overnight covering the entirety of the rocks. It progressed to a darker color at an almost hourly rate. I do not have pictures of it while it was in the tank but I'm including pictures of them outside of the tank. I'm using an led lighting fixture and only running the day lights for about 8.5 hours a day and running the blues for an additional hour. The LED's are only turned up to approximately 45% power.
Lastly what Potential tank mates might you recommend to add a little activity to my system if any?
<Please peruse the several "stocking reef" FAQs files on WWM. We have some 30k users per day...>
Ideally I would like a peaceful tank where everyone gets along.
Thank you again
<W. BobF>
RE: Chaos in my tank      4/23/16

<6 megs of pix; why? SEE, as in READ on WWM re algal ID. B>
RE: Chaos in my tank      4/23/16

It should have only been two small pictures of two rocks. sorry

<? Poisoned by BGA?>

Cyanobacteria or diatoms?      12/31/15
Hi, my system has been running for just over 6 months. Over the last three months I've had a very slow growing brown (?) on the sand only.
Twice I've siphoned it twice off the sand completely, and very slowly, over a period of possibly 2 - 3 weeks it will start becoming noticeable and unsightly again.
<Same ole.... >
Some characteristics:
It darkens through the day, but in the morning it is not visible.
It is only evident on the sand.
My Red Lipped Conches Eat it with relish.
<A good clue>
It isn't exactly what I would describe as a dust, nor is it a film.
It is a coloring of sand, that given time will develop short strands that will move in the flow. Picture included.
<Too large and no reading.... strike two>
It also has a tendency to climb up the glass from the sand, and when scraping it away my clowns and tangs hang around for every apparent tasty morsel.
Info on my system:
Alk 8.3, Ca 430, Mg 1310
NO3 0.1 on high sensitivity DD
PO4 0.02 on high sensitivity DD
I've had a constant battle to try and get nitrates higher, to at least 0.25, with no success thus far.
<Just feed a bit more is all I'd do>
In addition, I also experience red Cyano in my fuge under 6500k lamp. This I have deduced is due to my nutrient poor system.
If the brown growth is also Cyano, then I know it's cause - limited nutrients.
If diatom, I need to take a different course of action.
<See WWM Re, books I've penned.... need a microscope and sample to tell for sure. Very simple>
I hope you can help.
<Only you can. Bob Fenner>

re: Cyanobacteria or diatoms?        1 1 16
I cannot tell you how relieved I am to discover that it is impossible to identify by sight.
I'll dig out my sons microscope and see how good it is.
<Only need a few hundred power.... the lack of a nucleus..... BGA.... BobF>
re: Cyanobacteria or diatoms?        1 1 16

Thanks again Bob,
My son's microscope has done the job, and surprised me too.
It's not Cyano or diatom, it's Dinoflagellate.
<Ah ha!>
I could clearly see the difference based on Julian Sprung's pictures in his Algae book.
Most notably, the free swimming Dino within a tiny strand I retrieved.
<Yes; and a middling; girdling flagella as well if your optics and vision are good. A starch test (with simple iodine is further definitive>
I've never assumed it could be Dino as most Reefers have a terrible problem with them, and mine is just a light sprinkling. Must be due to the lack in nutrients.
<Possibly... though competition with other life forms, predation by small biota; could well be important>
To get rid of I'll do the following:
Continue to maintain low nutrients.
Turn my refugium light on 24/7.
Buffer my Alkalinity to about 10dkh which will raise my PH from 7.8/8 to hopefully 8.3.
If you could offer further advice on eradication, I'd be very thankful.
<Vacuuming the substrate, increasing RedOx by various means.... all gone over on WWM. Use the search tool for Dinoflagellate Control>
Best regards,
<And you, BobF>

Identification, ten megs, no use of WWM      12/27/15
What type of algae is this? It's only on my substrate and not on live rock.
<Read here: http://www.wetwebmedia.com/BryopsisF.htm
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?

Re: Mysterious algae or bacterial film. Please help!      12/5/15
Thanks for the response. I was mainly looking for an ID, and I mentioned the treatments, etc, to explain why I'm unsure what it is.
<And I responded that the only means to tell for sure was what? And what the likely sources of nutrient? TRY using WWM. B>
Re: Mysterious algae or bacterial film. Please help! /Earl?       12/5/15

Why do you think that I didn't try that first? I did, and I wasn't any more sure. After trying, I thought I'd ask the experts. But it seems like you were just annoyed. I'm sorry if I bothered you.
<A detailed listing of your water parameters, whatever you can test for, would be of a lot of use. There are a *lot* of faq's and pages of info about these nuisance/pest algae and bacteria etc. on the site here but we can't do a lot without more detailed, specific information. Your source water maybe, readings as per above, inhabitants, what kind of feeding you
do and of what. Also please note the file size limit we have to work with. Detail and close-up resolution is great but practical/functionality considerations are a reality. I recommend simply using image editing software (surely you use some for your camera...if not you can use GIMP which is good freeware). Maybe home in on demonstrative areas of the photos, crop them smaller to focus there, and be sure to "save for web" as a 72dpi file.>
Re: Mysterious algae or bacterial film. Please help!    /back to RMF       12/5/15

Why do you think that I didn't try that first?
<Because if you had you wouldn't have written>
I did, and I wasn't any more sure. After trying, I thought I'd ask the experts. But it seems like you were just annoyed. I'm sorry if I bothered you.
<Not a bother.... are you a non-native speaker/reader? Do you know what I've referred to as a "microscope"?
That this is the only way (apparent color won't do it alone).... DO please
re-read some of the articles and corresponding FAQs files on Algae Control on WWM; and write w/ specific questions. Bob Fenner>
Re: Mysterious algae or bacterial film. Please help!....         12/6/15

Is there a minimal magnification that you would recommend for help in identifying type/species?
<Yes.... 200-400X will do it....READ here:
It wouldn't be money well spent for me to buy a research-grade microscope if I only need it occasionally.
<Nah; a very simple QL series... do just read. About 30k people use WWM per day.... not able to re-key all>
Unfortunately, I don't currently have access to a microscope, which was why I asked for helping with an ID.
<Ask about at your local fish stores. Likely someone has one that they'll let you bring a sample in and use>
I'm sorry if I wasn't specific enough with that question. I received your other email about providing specific parameters, and I am currently doing tests to get these numbers. I should be sending that shortly.
<Ah good.... and that wasn't from/me... or signed... another WWM Crewmember, perhaps Earl. BobF>
Re: Mysterious algae or bacterial film. Please help!

Ah, I see. Thanks for the specifics.
Water parameters:
- SG 1.026
- hw-Marinemix reefer salt
- RO/DI (via SpectraPure unit) water
- TDS meter shows 0ppm
- Always replace DI resin when TDS shows 1ppm.
- pH 8.1, according to calibrated Milwaukee pH600
According to API test kits:
- Ammonia: 0
- Nitrite: 0
- Nitrate: 0
<Mmm; how is NO3 rendered zip?>
According to Salifert:
- Calcium: 390 - 400
- Magnesium: ~1170
- Alkalinity: 8.6dKH
After testing, I added a dose of Kent Tech M to get my Mag level closer to NSW.
According to Hanna Checker colorimeter:
- Phosphates: 0ppm (Do I need the higher sensitivity (ppb) checker?)
<No; assuredly not>
With a bloom, I'm not surprised that NO3 and PO4 are not detectable.
<Yes; possibly the mix of Protists, Monerans here is "sucking up" most all simple chem. nutrient>
Tank inhabitants:
- 2 percula clownfish
- 1 Cerith snail
- 1 red-leg hermit
- 1 colony of Zoanthids
The rest of the snails and hermits died during my dino outbreak 6 months ago. Waiting for stability (and necessity) before any sort of scavenger re-stocking.
Feeding regimen:
Formula 1 pellets, small amount (~10 small pellets) each day or every other day. I feed only a few pellets at a time to ensure that they are all eaten.
I'll send you links to better pictures to ensure that the attachments
aren't blocked for size, and so that you can see the entirety of the pics:
Thanks again,
<Mmm; well; there are a few "routes" you could/might go... for me.... I'd remove the useful biota, nuke/bleach the system and components (in place, including the rock, gravel).... ADD a large refugium, w/ a DSB there, on RDP lighting regimen.... and add a few lb.s of new live rock to restart; put the biota back in.... Bob Fenner>

Red Macroalgae ID?     8/28/15
<Seven plus megs.....?>
This is an algae update, better pictures and more samples, any ideas?
<Maybe a Botryocladia sp. BobF>

Re: Red Macroalgae ID?     8/28/15
Maybe the high res.? thank you for your time
<Heeeee! Welcome>
Sent from my iPhone
<I can't afford that. B>

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>

Red Macroalgae ID?      3/4/15
I've been doing research, but still don't really know what this is. I was hoping you all might know. Here is a picture: <font face="HelveticaNeue, Helvetica, Arial, sans-serif" size="3"><span style="-webkit-tap-highlight-color: rgba(26, 26, 26, 0.301961); -webkit-text-size-adjust: auto; background-color: rgba(255, 255, 255, 0);">http://imgur.com/twovS8z</span></font>
<Mmm; try attaching. Bob Fenner>
<Oh! http://imgur.com/twovS8z  did come up. Is a Rhodophyte of some sort.
Read here: http://www.wetwebmedia.com/redalgae.htm
and the linked files above!
Bob Fenner>

Algei      3/4/15
Hello i have a green algei growing in my saltwater tank and wondering what kind of algei it is and if its good or bad algei here's a pic thanks
<Appears to be a Green (Chlorophyte); but could be... BGA. Read here:
Scroll down to Algae. Bob Fenner>

Re: Algei      3/4/15
Thank you will snails eat it if i get snails
<Keep reading. BobF>

Difference between Calothrix and dinoflagellates?        1/5/15
Hello and happy holidays. I have a (hopefully quick) question: how can I tell the difference between Calothrix and dinoflagellates?
<Mmm; well; the former, Calothrix, is a genus of multicellular Blue-Green Algae (BGA), Monerans; more closely related to bacteria (Cyanobacteria) than the true algae; which includes the single-celled Dinoflagellates. The only way to really "tell" is to sample a bit and look at under a microscope... Both are best controlled through nutrient deprivation...
which can be brought about in a few ways.... gone over and over on WWM.
Read there re>
I have what is, most likely, one of the two on my rocks, and I am not sure how to tell the difference.
<Welcome. Bob Fenner> 
Re: Difference between Calothrix and dinoflagellates?       1/6/15

Thanks for the reply, Bob. I have been doing my best to deprive it of nutrients, and I have been using Chemiclean and UltraLife red slime remover in addition.
<Mmm; can be of use; though these antimicrobials are NOT my first choice/line of attack. Again, SEE/READ on WWM RE>

Those products don't seem to be doing much, except that they seem to be making the stuff extra stringy. But thanks for the info and I'll keep at it. I guess that discerning the difference doesn't matter with regard to the treatment.
Thanks again,
Re: Difference between Calothrix and dinoflagellates?       1/6/15

For whatever it's worth, those two products don't contain any erythromycin or antibiotics.
<... see my resp. below.... what does it state? Antimicrobials>

I am fairly limited in the amount of techniques that I can employ because my tank is an Innovative Marine
Fusion 20, which is an all-in-one with a rear chamber. I can run a small media reactor/fluidizer and a small skimmer. There are a couple of chambers to run sponges for mechanical filtration where I might be able to place small amounts of other types of media.
<Stop writing and start reading. B>

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>

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