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FAQs about Red Algae/Rhodophyte Identification 5

Related Articles: Red Algae in General, Coralline Marine AlgaeAvoiding Algae Problems in Marine System, Algae Control, Marine Maintenance, 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 AlgaeAlgae as Food

Related FAQs: Red Algae ID 1, Red Algae ID 2, Red Algae ID 3, Red Algae ID 4, Red Algae ID 6, Red Algae ID 7, Red Algae ID 8, & Red Algae 1, Red Algae 2, Red Algae 3, Red Algae in General, Red Algae 2, Red Algae 3, Red Algae Behavior, Red Algae Compatibility, Red Algae Selection, Red Algae Systems, Red Algae Nutrition, Red Algae Disease, Red Algae Reproduction/Propagation, Coralline Algae, Marine Macro-Algae, Use in AquariumsAlgae as FoodMarine Algae ID 1, Marine Algae ID 2, Marine Algae Control FAQs II, 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 ID       11/27/17
Hey guys.
Your site was recommended to me for algae identification.
This is a pic of it, its relatively rigid, grows quite well via sporing, breaks off sort of like lettuce, not Ulva and is of a high calcium content, not quite as rigid as capensis.
I found it diving ages ago and it reproduces well in my tank. Any help would be great, thank you.
<This looks to me to be Peyssonniella inamoena. Matte Red Crust Algae.
Mottled red and orange usually. Roughly fan shaped growths. Nice specimen and pic. Bob Fenner>

Algae ID, no use of WWM.... 4.5 megs of pix        11/20/15
Hello, I have something no one at my group can ID, Can you.
It starts out slow like a slim algae than turns into polyps that are rather though. also hard to scrap off. It is spreading fairly fast now.
What can I do. Thanks in advance, Paul
<Read. See WWM re Algae ID period, BGA (which I think the first two pix are) and Botryocladia; which may be the third.
Bob Fenner>

Question / ID       1/6/15
Attached? Is a photo of some rock I recently purchased. A friend told me to e mail you and see if you can ID the red growing on it.
Thank you
<Oh yeah; a Rhodophyte; perhaps a Fauchea species... useful and beautiful. SEE/READ on WWM re...
Bob Fenner>

red macro algae? coral? sponge?     1/16/14
Hi Crew - first, thanks for an extremely useful website - whenever I have a question that I cannot find an answer to - your site is one of the few places that offers exactly the right answer.
I have 60gal reef tank that I have been VERY patient with.  I started it up 9 months ago and just bought my first corals last week.  This was in part as I was fighting a diatom bloom initially, then a seemingly endless Cyano problem until recently.  The major reason for the Cyano die off/control now, was switching from an algae scrubber to a properly rated skimmer, and using only foods with low P content.
 This has helped immensely and I got to the point of being comfortable putting corals in.  Coralline growth has become markedly more prolific since then too.
<Ah, good>
Now my question is this: while fighting the various plagues (including a 300+ Aiptasia outbreak - thank god for berghia nudis), I noticed a really pretty hitchhiker on some of my live rock.  So this started growing during a time when even though my kit readings were essentially non detect, but the presence of Cyano/green hair indicated that I had a surplus N or P issue.  At first I thought it was a type of coral, and then considered sponges - but then someone on a forum suggested that it is likely a red macro algae - rhodophyte of some form?
<This is my guess as well (or a Foramiferan)... I didn't see (under magnification of your photo) any pores/openings... that would be present in Corals, Poriferans>
 It is a soft tissue, plate-like structure that is now roughly the size of quarter (with about half a quarter "depth" to it). There is a second larger example growing at the back of my tank, out of reach of a decent photo - that specimen is roughly two inches wide, an inch high and an inch deep.
Any thoughts?  Is it more likely a red algae?  Finally - this is the important bit: is it good or bad?
<Much more good than bad... mostly as an indicator of healthy conditions here. Not toxic>
 Should I be considering removing it, or if my water chem. is truly coming around, should this guy just die off/starve anyway?  Any thoughts would be greatly appreciated.  It's really pretty and I'd prefer to keep it if it isn't doing any harm...
and image attached for good measure too.
<Cheers, Bob Fenner>

Re: red macro algae? coral? sponge?     1/16/14
Well that's good news then!  Thank you so much for the speedy and reassuring response - you guys are the best!
<Ah, welcome Mark. BobF>

Gracilaria?    6/30/11
Hi crew, I purchased this piece of LR from my LFS a couple of weeks ago, specifically for the red algae growth which was less than 5mm at the time.
They didn't know what it was (big surprise, right?) so the sold it to me for much less than what I believe its worth! Anyway, the reason I bought it was to grow and harvest for my Foxface, but I would need to id it first. I believe its a type of Gracilaria, which would make it a beneficial feed for my fish. Am I right?
Its unlike Gracilaria I've had before, the kind I have had in the past has grown like a bush with thin stalks. These are flatter, not calcified, but just as red as any Gracilaria I've ever seen. Any thoughts on what species it is?
<Mmm, not one of the hundreds of species of Gracilaria, but a Rhodophyte...
Read here: http://www.wetwebmedia.com/redalgae.htm
and the linked files above>
<Bob Fenner>

Red Algae?, ID, 8/14/08 First off, thanks for all the info that you have on this site to help us stupid people out. <Not stupid, just in need of some direction, we've all been there.> You have helped me out of several issues. Not sure what I have here as I cannot find a pic on the site. First the basics, 65 gallon reef tank with live rock and a 25 gallon mud filter system that has been up and running for over 2 years now. Only 2 fish a maroon clown and a damsel. Regular water changes with RO water being the source and regular chemical maintenance. Lighting is fluorescent on for about 8 hours a day. This "algae" started in one area and I tried physical removal which seems to have caused a multiplication of this growth in large quantities. I have included some photos please advise if you can identify and what treatments you recommend to slow or cease its growth depending on the situation. Thank you in advance for your advice. Chris <Is a species of Botryocladia most likely. I have this in my own tank, does spread but does not seem to be aggressive as Valonia. Same control as any other algae, nutrient control, water changes and manual removal. I usually try to snip off large clusters at their base with scissors or a razor when I do water changes. It just takes some time and discipline to get it under control.> <Chris>

Red algae taking over 30g reef   4/27/08 Hi there, This is my first time asking a question on this site although I've referred to it many times...amazing resource! <You are a stranger here but once. Welcome> I have a 30g reef tank that has been running for just over a year. I have about 50-60 lbs live rock, 1" aragonite sand base, a Bak Pak skimmer, 2 MJ900 PHs, and the lighting is 4x39 watt T5HO. I have a variety of corals, mostly softies (zoos, mushrooms, leathers, GSPs) plus a Platygyra brain coral and a frogspawn. Most of the corals are doing pretty well. Lots of coralline on the glass and starting to cover a good portion of the rocks now. Critters include feather dusters, hermits, a variety of snails (Nassarius, Astraea, Cerith and Nerite), a serpent star, a cleaner shrimp and 2 fish, a Pygmy angelfish and a Falco Hawkfish. Until just recently I also had a 6 line wrasse but he went carpet surfing despite the egg-crate on the tank :-( I do biweekly 5 gallon water changes, my SW is made with DI water and Reef Crystals. <Sounds/reads very nice> My problem is a nuisance red macroalgae that is taking over my tank. I can't seem to find any pictures online that resemble this stuff close enough to make an ID. It's driving me nuts.....shading and bothering some of the corals and catches lots of detritus. I yank out as much as I can but it grows on everything, including the glass, the powerheads as well as the rocks. Interestingly, some rocks in the tank seem to be more affected by it, while others are relatively clean. <A clue... what sorts of properties here would favor the algae? Or disfavor it on the others?> I have 4 rocks that came from Tampa Bay saltwater and they do not have any of this stuff on them. I don't know what I can do to get this stuff under control; my tank is too small for a tang, and none of my current critters will touch it. Was thinking of Turbos or maybe an urchin but I'd really like to get an ID on this stuff before I make any bad decisions involving a critter. Pic attached.....thank you for your help! -Brooke <Is almost certainly a "true" Rhodophyte... my guess is on the genus Fauchea, or of its Order. Please see here: http://wetwebmedia.com/redalgae.htm and the linked files above re Control (Compatibility). Bob Fenner> Brooke Longval Marine Ecosystems Research Laboratory Graduate School of Oceanography Narragansett, RI 02882

mystery growth -- 03/20/08 Hi, <Mike> I have searched in vain for something to help me ID this red growth. My clowns seem to like it and it's off in a corner of my reef and growing slowly. Any ideas? Mike <Is a Rhodophyte, a Red Algae... perhaps a Rhodymenia... Read here: http://wetwebmedia.com/redalgidfaqs.htm and the linked files above. Bob Fenner>

Please help ID this: Nemastoma - 2/24/08 Hi WWM crew, <Good evening, Mitch!> I noticed some type of growth from my live rock in the last few weeks, and wanted to see if you had any thoughts as to what it may be. <Okay> I first thought it was a macro algae, <Heeee! First impressions are often correct!> ..but it looks more like an animal, with its sheen and what looks like cell structure. Tank (180) is doing great, SPS growing well, all levels good. I am thinking this is a good thing, just have no clue what the new life is. <It's a red algae called Nemastoma, and I think very pretty! Please see the FAQ/photo at this link under the title 'Red Algae IDs 8/2/03' for comparison: http://www.wetwebmedia.com/redalgfaqs.htm > Thanks for your thoughts....... Mitch
<You're very welcome! Take care, -Lynn>

ID please: Rhodophyta - 1/5/08 Hello Crew, <Hi Kelsey!> After much searching, I have not been able to figure out this "weed" that has been growing rampantly in my tank. First, tank specs: The tank is a 24"x24"x20"h lit with 250W HQI. I have a refugium, skimmer and closed loop with an OM 4-way and carbon running in a reactor. The Live Rock was ordered from Fiji in April uncured. I cured the rock in bins and set up the tank in July. I have been manually removing as much as possible but this stuff is everywhere. <Yikes!> Any help as to what it is good or bad, and what the proper control for it would be greatly appreciated. <It looks like a Rhodophyte of some variety. I saw a couple of photos of Acanthophora spicifera that looked similar (http://www.sms.si.edu/irLspec/Acanth_spicif.htm), but there are other possibilities as well (Hypnea, Laurencia, Chondria). All are known to be around Fiji. Bottom line is that in your case, this species is invasive and you need to get the upper hand on it!> Is there any biological control or just manual removal? <Best thing to do is track down/eliminate the root cause of the rampant growth. Make sure you've got your nutrient level under control and employ aggressive manual removal. Please see this link, as well as, related links at the top re: http://www.wetwebmedia.com/nutrientcontrol.htm http://www.wetwebmedia.com/avoidingalgaeproblesm.htm .> As always, thanks for your insight and time. <You're very welcome! I know what it's like to fight an invasive algae. It can be frustrating and time consuming, but with enough determination you'll get through it!> Houston, TX
<Take care --Lynn>

Red / Purple/ Maroon Hair Algae? Nutrient Control 11/15/2007 Hi WWM crew. <Hello Jurgen, Mich with you tonight.> I've been reading and your site for a while now, and has given me tons of information when I was setting up my first reef tank. <Glad you have benefited.> It's been almost a year now, and it seems to be doing great. <Happy to hear!> But now, I need some expert help and guidance myself. <OK.> I've got this annoying algae growing in a few spots. It started to appear in some very high flow areas at first (sump return area, on the rocks in front of my closed loop outlets) but in the last couple of weeks I see it appear in some other random spots on my rocks. It's not growing very fast, but it is slowly but surely growing. <Happens.> so far, nothing seems to make it go away. <Nutrient control is usually the key. Some suggestions here: http://www.wetwebmedia.com/nutrientcontrol.htm http://www.wetwebmedia.com/scottsh2ochgart.htm http://www.wetwebmedia.com/watchgantart.htm http://www.wetwebmedia.com/water.htm http://www.wetwebmedia.com/refugium.htm > my water parameters seem to be all right. <Vague.> - 90-gallon tank, with 29g sump. - EV180 skimmer - plenty of random water movement using an oceans motions device and some small MaxiJet placed inside the tank. - 8 x 54W T5 lighting; 4 bulbs (two actinic, one aquablue, one actinic+) on for 8 hours a day, all 8 (two more aquablue and two more actinic+) on for 5 hours) - do a "reasonable" water change every weekend, sometimes (depending on my schedule) every other weekend. - only use RO/DI water that tests at 0 - nitrates tested <5 mg/L (Hagen Nutrafin kit) - phosphates tested undetectable (Salifert kit) - SG is 1.025 - temp is steady at 78F 24/7 All my corals (LPS, SPS, zoas, mushrooms) seem to be doing just great. <Good.> I barely have any hair algae at all (lawnmower blenny starved to death unfortunately) <Very sad. I'm sorry for you both.> The only algae that I seem to be able to grow is this nasty purple stuff, and some bubble algae, which my emerald crabs won't eat either, but that is not as annoying right now. <Keep on top of the Valonia, it can become problematic.> none of my herbivores seem to even look at it either; <Not surprising.> I have a few scarlet hermits, a few blue-legged hermits, Cerith and Astraea snails (I believe one of the Astraea had this red hair on the shell when I got them, getting it into my tank that way) <Many possibilities.> emerald crabs don't look at it, Tomini tang doesn't look at it... <OK.> I don't feed very much, and not very often. three to four times a week, one cube of frozen food (nicely rinsed first) and some live brine every now and then. <The brine have little to no nutritional value.> some pellet food every now and then, but more as a snack, nothing to fill them up with. <OK.> I'm attaching two images, I hope you can help me out and point me in the right direction to get rid of this stuff, before it takes over the tank. <Looks like red hair algae, possibly Polysiphonia.> PS: yesterday, I threw two things in my sump, <Hmm, hopefully they were things that belonged there!> just in case it might help, as I don't think that it will hurt at this point. - a bag of Kent Phosphate sponge (the ceramic type media) will replace that one tonight with a new batch. - a 100ml bag of Purigen (will leave that one in there until it starts to discolor) Best regards, Jurgen. <Please next time use proper capitalization, i.e. "I" not "I" Cheers,

Gracilaria Questions, species IDs  9/6/07 Hi Crew, Let me start off with the obligatory "you guys rock" complement (because you do). <Haha thanks> I've asked you a handful of questions since I started reefing and have always been given solid advice. I always feel a bit intrusive about asking another question, but I promise I looked high and low for the answer to this one. If I never see another scientific paper again, it'll be too soon. I'm hoping others will find this question useful to them. <:-)> So here goes. What's the difference between Gracilaria parvispora and Gracilaria Pacifica? <Not much. They're very similar and both have the same common name "Ogo." They branch a little differently and are each more common in different areas (Gracilaria parvispora is from Hawaii).> Is one better for tangs than the other? <I highly doubt it.> I'd like to switch the macro I use for nutrient export over to Gracilaria <probably a bad idea> (currently using Chaeto) but not sure which to go with (or if it even matters?) I plan on feeding some of the extra growth to my tangs and blue-faced angel, who all eat tons of Nori at the moment. <Aquaculture of this stuff is difficult. The mariculture farms that grow it float baskets of it in ocean water.> I know Indo-Pacific Reef Farms is always highly recommended, and they seem to be the only ones that carry G. parvispora, but it's really expensive! <Hmm... G. parvispora is common. It's eaten by people too. Try looking for "Ogo."> Every other online dealer I've found carries G. Pacifica at reasonable prices but no G. parvispora in sight except for at IPSF. Should I save my money or is there a reason to splurge on G. parvispora? <Unless you're going to eat it yourself, I see no reason to insist on G. parvispora.> Also, any quick tips on growing? I plan on putting it where my Chaeto currently is, which sees about 1200gph tumbling in from the display above-very turbulent and bubbly. For lighting I'm currently using a 32W 6500k fluorescent screw-in about three inches from the water's surface. It has a good reflector, and I run it on a 12 hour photo period. In case you ask, I have a clear acrylic lid between the light and the water so it doesn't splash up. <See above. I wouldn't even bother trying to grow it in a home aquarium.> Best to you all, <Best,
Sara M.>

New Print and eBook on Amazon

Marine Aquarium Algae Control

by Robert (Bob) Fenner

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