Algae ID ... Are They Dangerous... Can Be Problematic... 12/06/2007 Dear WetWebMedia -- <Dave and Laura> Thank you for all your help! <Welcome!> We love your website. <Great to hear!> Unfortunately, we lost our pulsing xenia recently to unknown causes. It came with our live rock and seemed to be thriving until suddenly crashing. <Not uncommon I'm afraid... Xenia can be fickle... For some it's a weed and for others it's impossible to keep alive.> Now it's gone, faded back into the rocks... ): Nothing else looks bad, but we're concerned about some recent new algae. <OK.> Stats: 55 gal tank, good flow, <Vague.> 4x65W 10k & actinic bulbs, FOWLR 5 fish (3x dartfish, <Many species of dartfish, and some of the more common ones will fight to the death with conspecifics, for instance only one Firefish (Nemateleotris magnifica) should be kept in a tank of this size as more than one will usually fight till there is only one left.> 1x diamond sand goby, 1x fairy wrasse) 1. Attachment: fernlinkealgae.jpg neardiscosoma.jpg We recently discovered this fern-like algae (we assume it's an algae) growing in a number of places. It looks kinda cool and doesn't seem to be interfering with anything. First question is: What is it? <It is an alga and looks like Caulerpa taxifolia to me.> It looks like the pictures in the books of Caulerpa, but we can't tell from the books if its dangerous or not. <I would remove this from the main displace can quickly and easily become invasive.> One reason we're concerned is that it is near our Discosoma. Second question is: Could it hurt the Discosoma? <Yes it could.> (The Discosoma also appeared on our live rock and even moved from another less stable position to this one, so we're rather fond of it and wouldn't want to see it hurt.) If we need to get rid of it, how do we get rid of it? <I would remove by hand. Will be a tedious process... just keep picking. And please dispose of it responsibly so that it is not accidentally introduced to the local waters.> We don't want to take the rock out of the tank since the dartfish have nested underneath it. <In the log run it may be easier to remove the rock.> 2. Attachment: poriteINtrouble.jpg The other coral that appeared on our live rock is this Porites, but we're concerned that it is in a fight with nearby algae. <It is.> The Porites reappeared on what looked to be dead rock and regrew. It seems to be getting enough light and enough flow but the algae got a foothold on some not-yet-coral-encrusted parts. We're concerned that the algae (ok but not cool) is fighting the coral (really cool). <Yes.> Obviously, we want to help the coral if we need to. <Again manual removal will help, as will decreasing the nutrients in your water and employing a beneficial macroalgae such as Chaetomorpha in your refugium or sump. More here: http://www.wetwebmedia.com/nutrientcontrol.htm http://www.wetwebmedia.com/algaeconMar.htm http://www.wetwebmedia.com/avoidingalgaeproblesm.htm http://www.wetwebmedia.com/scottsh2ochgart.htm > 3. Attachment: brownalgae.jpg We've seen some of this stuff appearing and we can't agree on what it is or if it's good or not. Any help? <Looks like Lobophora variegata to me.> (If we need to get rid of it, how do we do that?) <Again manual extraction and nutrient control.> Thanks again for all your help <Welcome!> Love your site <Nice to hear!> Dave and Laura <Mich>

Question on Macro-Algae 11/30/07
Hi WWM Crew,
<Hello>
Can you give me your thoughts on a good species of macro-algae for use in a refugium? The articles on WWM appear to recommend Caulerpa. However, I am looking for something palatable to most herbivorous fishes. Does there exist any palatable, non-calcareous (or just low maintenance) macro-algae that do a good job of nitrate/phosphate removal?
I have been asking this question to a number of people, and the following algae have been recommended to me:
+ Gracilaria
+ Ulva
+ Sargassum
+ Caulerpa
+ Chaetomorpha <Two thumbs>
Please advise.
Thank you for your time,
M. H. Arian
<The Chaetomorpha is your best bet for all the attributes you are looking for. Fish can and will eat it, fairly low maintenance, and grows fairly fast for nutrient export. Caulerpa has been the mainstay for aquarium use for years mainly because of its growth rate, but Chaetomorpha is has gained popularity over the past few years. Happy reefing, Scott V.>

Macro-algae in the Main Display Tank 10/17/07
Hello,
<Hi Ryan, Mich here.>
What would be the ideal macro-algae to keep in the main display tank?
<Depends on what purpose you want it to serve.>
I understand it is preferred to keep macro-algae in a refugium,
<Generally yes.>
but I wont be getting one soon
<Aren't hard to make... large Rubbermaid type containers work well.>
and would like to try additional ways to combat the green hair algae in my tank.
<Increased frequency and volume of water changes, decreased feedings and macro algae/refugium would help.>
Halimeda sounds like the best candidate so far.
<Is an option but can get out of control. For what you want you may want to consider Chaetomorpha.>
The downsides seem to be its calcium requirements (the coralline algae already has enough competition with the hair algae) and I've read it does not handle pruning as well as others.
<I have found it to be quite hardy, if not too hardy in the main display.>
Are there alternative macro-algae worth considering?
<Yes, Chaetomorpha is a good alternative. It will serve as a good nutrient export, generally does not become invasive and is relatively easy to control/remove from the display. I would avoid Caulerpa in the display at all costs.>
Thanks,
Ryan
<Welcome! Mich>

Sump plant confusion. What’s the best macroalgae for a sump – 09/02/07
Hello crew,
<Hi Dan.>
I have been doing a ton of reading up on what plants to keep in a refugium/sump. I am looking to really use it for de-nitrification. From reading Chemo <You mean Chaeto? Like in Chaetomorpha.> seems to be a good choice, but I have read that is not that great for reducing nitrates as some would say. I have also read that Calupera <Probably Caulerpa> is good for de-nitrification, but it goes sexual monthly <Not necessarily monthly...it strongly depends on growth, size of the algae and the time since it was cut.> and releases caluperin <Caulerpenyne> into the system, which is not a good thing either, also if it is broken or turn it will do the same thing. What is the best bet to put in there to reduce nitrates, without messing with my chemistry?
Thanks Dan.
<Short answer: Chaetomorpha. Long answer: Chaetomorpha grows slow in some systems, but still provides sufficient nitrate export. It may double its size in about one or two months in general and does not cause any problems in a sump I am aware of. In a display, however, it can be hard to control and grow between corals like a weed. Caulerpa species can grow much faster and therefore export the same amount of nitrate in a shorter time. However, as you noted, they may release substances (one of them being Caulerpenyne) slightly toxic (and poorly understood) or go sexual and release all the nitrate they have taken up into the water again. To prevent that, Caulerpa needs to be cut on a regular basis (about 4-8 weeks). One careful cut usually is enough to divide the algae and take half of it out of the system. If you are careful (versus acting like a lawn mower) not much fluids from Caulerpa will get into the tank. I have many different macro algae, but Chaetomorpha is the most easy going among the somewhat faster growers. Think about a DSB in the sump, too. See also http://www.wetwebmedia.com/ca/volume_3/cav3i6/Algae.htm and the linked files at the bottom. Cheers, Marco.>

Moss... ? Do You Mean Algae? Nutrient export   8/23/07
Hi Crew,
<Hi Alan, Mich helping out.>
Just a short question. Will moss take in nitrate?
<Mmm, not sure what you're referring to as moss. I presume you don't mean the kind that grows on rock in the woods. But I'm not sure what you're referencing here.>
My purpose is to put it into my sump and hopefully will help to reduce algae growth.
<There are beneficial macro algae that will fill this role quite effectively. I, personally, would avoid Caulerpa. My favorite is Chaetomorpha. It generally grows well and is easy to find. Gracilaria is another excellent choice. You can read more here and the related links in blue:
http://www.wetwebmedia.com/greenalg.htm
http://www.wetwebmedia.com/refugium.htm >
Thanks in advance.
<Welcome! Mich>
Cheers
Alan

Cycling Tank, When to Add Macroalgae. 6/6/07
Hey Bob,
<Mich helping out today.>
I have a quick question. I've been cycling my new 180 for about 2 1/2 weeks now.
<Congrats on the new tank!>
The Nitrites are just about zero now, the pH is a little low, I'll just get some buffer for that.
<Ok.>
Anyways, when should I add micro algae to the refuge?
<I think you mean macro algae...>
This is my first refuge/sump, I already have mud in it w/LR, and about 200 lbs of a dead rock/LR mix in the tank with a 1/2 inch sand bed.
<You can add the macroalgae now.
Cheers,
Mich>

New LR Caulerpa control... pre-emptive strike? Nah... violence is the last refuge of the incompetent... Yes Georgie-buoy, am talkin' to you   2/13/07
Hello Bob,
First off I would like to tell you that your books have helped me tremendously over the years, I have grabbed every one I could find! I recently  set up a 90 gallon reef aquarium, 1 week ago to be exact. My tank has a mix of Marshall Island LR and Tonga Kalani, and Tonga branch rock, and about a 2"   aragonite sand bed that rises to three inches in the rear of the  display.
<Mmmm, you may want to increase... or decrease these depths a bit... Please see WWM re: http://www.wetwebmedia.com/marsubstr.htm
the linked files above>
The rock was hand picked by myself and put in curing vats for  5 weeks with heavy circulation, a turn over rate of 14 x an hour and  heavy protein skimming. The display has no trace of ammonia, nitrites,  nitrates, or phosphates and has a turn over rate of about 12 times an  hour. Calcium is at 450, dKH is at 12, aquarium temperature is kept between  78 and 80 degrees F. The lighting system on this 90 gal tank (48 x 18 x 24)  is 2 x 250 watt 14 K metal halides that run 8 hrs daily and 2 x 96 watt power  compacts 7100 k that run 12 hrs daily. I also run 4 watts white moonlighting on  this tank every night. The lighting system is fully automated and the tank for  all intents and purpose is running very smooth, there is quite a bit of life  already stirring in it. My big question for you now that you know most of the  info on this aquarium is; On the Marshall island live rock there are a lot of  sprouts of what appear to be Caulerpa sertularoides, or Caulerpa  taxifolia, the only other photo on wet web media that I saw that resembled  what I have is Caulerpa mexicana but I have a feeling its one of the  two previously mentioned.
<Yes... at least not C. mexicana>
I plan on keeping SPS corals in this aquarium and I am  worried this particular algae growth might become a problem. Should it be left  alone in the aquarium to grow and be pruned?
<I'd engage bio-warfare some time hence>
it isn't terrible looking stuff, or  should I strike now while it is in its infancy?
<Nah... not likely to do much good at this point>
Any advice you have on this  dilemma would be greatly appreciated. Thank you for your time.
Brian  Crenshaw
<BobF>

Macro-Algae Oxygen production   2/6/07
Greetings all,
<David>
I have a bit of a complicated question.  I'm sure you can help.  I'm looking for information that compares the different species of Macro Algae (commercially available) in the field of Oxygen production.  
<Mmm, not posted on the Net as far as I'm aware... such data must, of course, "spell out" the given conditions of comparison...>
I have seen systems where for some reason the water movement shuts down.
With zero water flow, zero surface break, stale water. Fish and other creatures have consumed the oxygen in the system in just a few hours.
Meanwhile systems in the exact same circumstance, that have healthy macro algae populations, have been able to provide oxygen for the resident bio-load and assist in sustaining life.
<Let's speculate on what the differences might be here... some essential nutrient? Temperature?...>
The only other piece of information I was wondering about was of the different species of macro algae which require the least amount of lighting.
<The Reds least of all as a Division, then Browns, Then Greens...>
Thanks for all your awesome help.   
Cheers,
David
<Can't be more specific w/o more specific questions. Bob Fenner>

Caulerpa ?   12/29/06
Greetings,
<Salutations to you!  Mich here.>
I've been attempting to use a CPR AquaFuge stocked with Caulerpa and some live sand to help control some nitrate problems in my 60g saltwater FOWLR.  
<Good idea.  I would choose Chaetomorpha over Caulerpa as there is less potential for problems with this macroalgae.>
Right now there is so much Caulerpa in the fuge that it protrudes from the top of the fuge and the lights ( on for 24 hours) bake it into this nice white sludge.  
<Nasty!>
I'm planning to cut a bunch of it out, how much do I need to act as an effective means of lowering nitrate?  
<I would keep as much as you can comfortable fit.  No need to keep it crammed packed.  I would not cut the Caulerpa, tends to release toxins when cut.  Instead, just tear it by hand.  I would also keep it trimmed to below the waterline.>   
Thanks,
<Welcome!  -Mich>
Jason

Re: Chaeto - looking for the green shoots of success  - 04/19/2006
Hi Chris!
Yep- I meant to say ditch the Caulerpa!" I noticed that the other day and thought "What was I thinking?" LOL!
I know that Caulerpa has been known to release some compounds that have been shown to inhibit coral growth, so it's not outside of the realm of possibility that it's doing the same to the Chaetomorpha...I really would get rid of the Caulerpa, myself.
Hope all goes well!
Regards,
Scott F.

Clown Surgeon, other Tang... comp., macroalgae avail.   4/1/06
Thank you Bob, that cleared it up somewhat. Also just wanted to ask if you have received an email I sent a week ago. Not sure if it got lost or something?
<Don't recall... anything that was missed... lost...>
I know you're busy, so if the reason is due to the backlog of questions, I apologize for my impatience.
I have included the email here:
<Ah, good>
"Hi Bob,
I am considering purchasing a Clown Surgeon (Acanthurus lineatus) and have researched widely on this fish. I would like your opinion on whether it will be suited to my tank. I have a 900 Litre tank currently housing a blue-spotted ray, and 3 small snowflake eels. I plan to complete the tank with 2 blue-lined snappers and 2 H. acuminatus. Do you see any possible problem if I were to introduce a Clown Surgeon?
<Mmm, not with what you list. This may become a/the alpha fish here>
I understand they are aggressive and require a higher level of care. And I am concerned it might cause trouble with the snappers. If I don't get the Clown surgeon my other option is an Acanthurus Sohal or a Naso Lituratus.
<These can also be "bold", particularly the Sohal>
I know that this is involves a high degree of speculation, but I am trying to avoid possible personal disappointment and stress for my tank
inhabitants. Have you had any experience with this (these) fish?
<Oh yes>
Also, I am having trouble finding any retailer in Australia which sells Chaetomorpha...Can you suggest any way in which I can get my hands on some?
<Perhaps some other hobbyist... are there BB's for the marine aquarium hobby? I would query otherwise re on Reefs.org, Aquarium Frontiers, ReefCentral re...>
(Am also not sure on the current legality of importing/retailing this type of macroalgae.. I have emailed Aust. Quarantine but so far no reply)
<Do take care to not break the law>
I do have access to red macroalgae however, and I was wondering if red algae is suitable for consumption by any of the above mentioned surgeons.
<Many species of Reds, yes>
Will (can) it also serve as a denitrifying component in my refugium?
<Definitely>
Thanks in advance,
Joe.
<BobF>

Non-Calcareous Tang "Safe" Seaweed - 07/29/06
Hi gang,
<<Hello Chuck...EricR here>>
I wrote back some months ago describing a problem in my  'display' macro tank. . . Which Dr. Bob correctly diagnosed as 'blue green algae' (despite its reddish/hairy appearance).
<<Mmm, yes...comes in a myriad of colors>>
His prognosis was accurate -- albeit somewhat discouraging -- that I was unlikely to be able to eliminate this troublesome nuisance, since it tends to bend systems to its own design.
<<Pretty smart fella, that Bobster>>
After several years of way-too-much maintenance, I finally/reluctantly reduced the tank to a large field of red seaweed (Gracilaria morph? Not sure. Looks like 'fire' -- but in opaque strands which form clumpy 'bunches' rather than the
translucent 'Halymenia' I used to have) along one side. . . separated by a large, open field of white aragonite from an enormous cream-colored double Rasta (slightly larger than a football, and host to a pair of true Percs) on the other side.  The happy end result?  The simple fire-and-ice look of the overall tank (a 60 gallon) now gets compliments. . . whereas my previous
efforts at maintaining a seaweed 'zoo' looked pretty darn bad.  The second bit of good news was some Sargassum (hystrix?) <<one possibility>> which I'd cultivated in the system that got overrun was transferred to my main reef. . . where my gluttonous yellow tang and purple tang were good about 'scrubbing’ off the troublesome blue green algae (something they seem happy to consume in small amounts). . . and after a few test-nibbles of leaves and stalks, are leaving the new crop of butterscotch-colored leaves to grow without disturbing them.  I realize this isn't a plant that is commonly available (I got mine from a hobbyist for a few bucks on E-bay), but for a guy who thinks the idea of seaweed in a reef tank is cool, and still loves tangs, this is a real plus.
<<Yes, so it seems>>
I keep mine anchored to several bits of live rock and down on the
substrate, to minimize interference with my corals. It's a long way from the lights (about 25 inches down from my just-PC's lighting) but is growing just fine.  Sorry for the uncertainty with respect to names. . . but most of the LFS labels run along the lines of 'red kelp. . . or 'green macro'.
<<Indeed>>
Chuck
<<Thank you for sharing.  EricR>>

Macroalgae Selection   6/13/06
Hello
<Hi there! Scott F. here today!>
Do you have an opinion on any type of macroalgae that can be used decoratively in the main display? Someone has suggested Halimeda  from Live aquaria.
John Arenz
<John, as long as you are maintaining sufficient calcium  and light levels in your system, I think that you'll do fine with this macroalgae. It's one of my personal favorites!>
 

Putting Macroalgae In The Mix!
Hi Guys,
<Hey! Scott F. your guy tonight!>
What macro algae do you recommend for a refugium.  Caulerpa doesn't seem to be the best choice.
<Ahh...My fave is Chaetomorpha linum. It's a wonderful macro algae that is both attractive and prolific. It is relatively undemanding, too- and does not have the tendency to release sexual products into the water like Caulerpa. It looks for all the world like one of those pot-cleaning scrub pads...Really neat stuff>
And does micro algae create any type of plankton or food for corals?  I was  under the impression it does but I was told at my LFS that this is not so.
<Well, you're both right...Although the macro algae does not "create" plankton, it does provide foraging and living area for a variety of organisms, who reproduce within the "canopy" that the macro algae provides. As such, it is a great "habitation space" for planktonic organisms and epiphytic materials. There are many benefits to macro algae use in refugia- this is just another one!>
Thanks for your time I love your site. Chris Dial                                                             <Glad to hear that, Chris! We really enjoy bringing it to our fellow hobbyists each and every day! Grab that macro algae and get going'! Good luck! Regards, Scott F> 

Ulva for Refugium
Hello Crew,
Is Ulva a good macroalgae for nutrient export in the refugium?  I have a bunch growing in my refuge but don't know if I should crop it or not.
Thanks for your help.
Roy
<Ulva and Enteromorpha (Order Ulvales), aka Sea Lettuce are excellent green algae for refugium use... for nutrient export as well as food. Bob Fenner>

Macroalgae out of control
Hi there
<< Hi. >>
I am having problems in my reef aquarium with macro algae growing rampant. << This isn't a problem, you should learn to love algae like me. >> I've always had a small patch of macro growing on some live rock since I started my reef a year ago. It has always struggled to flourish. The last few months it has taken off to the point I pruned it from the rock it originated from. Now it has spread to various rocks and competes for space with my zooanthids which I don't like. << I don't like Zoanthids either. Just kidding I know what you meant. >> It looks like a miniature Elkhorn fern or Staghorn fern if you are familiar with that, It has branching leaves. I also have these hard green patches of calcareous algae growing too much. I do weekly 10-15 % changes and I have an ev120 and refugium packed with Chaetomorpha that grows great. I feel its a nutrient problem but my nitrites are only 5ppm. can I remove the rocks and scrub off the patches of pesky algae?? << Yes you can, but I wouldn't. I'd either do nothing, or maybe increase my herbivore load (like Rabbitfish or emerald crabs) which are known to devour this stuff. >>
<< Blundell >> 

-Refugium & Macroalgae question-
Hi, Larry here. <Hello, Kevin here> I have a 120g FOWLR tank with a remora pro skimmer and 2 BioWheel 400 filters and power heads for extra water flow.  I have about 40lbs of live rock as well.  I just purchased a CPR 19" AquaFuge which hangs on the back of the tank to help with nutrient export and help keep my nitrates down which are running around 30ppm. <Remove the bio-wheels, problem solved!> My goal is to lower the nitrates to 15-20ppm. <Why not to undetectable?>  My fish are all healthy and I am not feeding too much.  The tank is stocked with a blue tang, purple tang, flag fin angel, false eye puffer, Heniochus, tomato clown and a cleaner goby so I don't think its over stocked.  My nitrites and ammonia are always 0.
My questions are what type of media do you recommend for the refuge- live DSB or mud and what type of macro algae are most efficient at using up the nitrates? <My preference has been to use a DSB, but mud 'fuges work well also. Chaetomorpha is my favorite macro as it is not nearly as much of a pain in the butt as Caulerpa is.> I know that adding more live rock to the tank would help but I don't plan on adding more than another 15-20lbs. Currently I change about 18g of water every 6 weeks and don't plan on changing more often because I have enough work to do maintaining a 75 reef tank.  My tank is 1 year old and all the fish have been doing well.  Thanks, Larry in Minnesota gearing up for the 4 month deep freeze. <Good luck1 -Kevin>

Source for neat plants, algae and sea grasses 11/30/04
Hi Guys, Been reading your stuff for quite awhile.
<cheers>
I'm getting ready to set up my next tank and would appreciate a little input. It's a 375g - 96x30x30 that will incorporate a 150g sump (dual protein skimmers plus any other filtration stuff) and a 150g refugium. Lighting will consist of 2-250w MH HQI 14k & 2-250 MH HQI 10k plus some various PC lighting for dusk/dawn effect. I will be using a DSB in both the tank and refugium. Sorry, but it will be a somewhat mixed tank - primarily SPS with a few softies and a minimal fish population. My original plan was to incorporate the tank DSB with sugar fine sand,.2-1mm, (6") and grow some sea grasses in it, which brings question #1 - is this suitable for Syringodium or stick to Thalassia ?
<the latter is easier to get and keep (its shorter and better suited for aquaria)>
The refugium would use fine sand,1-2mm, (7")with some Halimeda and Penicillus, which I think would harbor more 'pods for export to the main tank.
<actually... Chaetomorpha would be best of all>
What kind of flow should I have through the refugium ?
<something around 20X turnover or better for vegetable filters>
I plan for a total of about 6000gph with most of it going through the sump.
>may not be enough flow for the display (depending on the exact coral species you keep... especially for SPS - need 20-40 X minimum)>
Sound reasonable or should the 2 DSB's be switched?
<I don't follow here>
Any other observations would be great. Regards, Greg
<I just bought Thalassia, Chaetomorpha and more from www.billsreef.com. Fab chap from NY area. Covers plants and algae and knows his science. Do consider. Anthony>

Dictyota for Nutrient Export?
I was wondering if Dictyota can be used for nutrient export in the sump or is it more of a plague? My LFS has some for free but didn't want to get it before I knew what it was, its the blue green species of it
thanks
<Hi!  Dictyota is highly noxious and is a poor choice for nutrient export.  Chaetomorpha is much better in this application!  You know what they say about a free horse...Cheers, Ryan>

Macroalgae In The Mix!
WWM:
<Scott F. at the keyboard this evening>
I’ve been reading through your FAQs on the Ecosystem Mud filter approach. Since these are not dated, I can’t tell what is the most current line of thinking, but did note that there seems to be mixed feelings on this even among your staff. That’s fine and perfectly understandable.
<Good, 'cause we do all have different opinions based upon our own experiences, which gives our fellow hobbyists an honest point of view.>
New information comes along all the time. Can you give me an update on the following questions:
<Will try!>
1. I see a lot of conflicting info on use of Caulerpa. Toxicity, etc. Is it still recommended?
<Caulerpa is a great macroalgae that is prolific, easy to care for, and good at exporting nutrients if carefully harvested on a regular basis. Nothing is new here...It is prone to "go sexual" and release its cellular material into the water under the right circumstances, and some also theorize that it may produce substances which are potentially toxic to some corals. I prefer more "benign" macroalgae, such as Chaetomorpha. In addition, it is actually illegal to keep in some areas, such as Southern California, where it has been released into the wild, to great disdain.> 
<Editor's note: Under State law (Assembly Bill 1334), the sale, possession, and transport of Caulerpa taxifolia was prohibited throughout California in September 2001. Please see here: http://www.swrcb.ca.gov/rwqcb9/programs/caulerpa/caulerpa.html >
2. Is it okay to use a micron sock and prefilter sponge with this system? Do these remove the desirable critters?
<In my opinion, using these filter socks is fine; you just need to clean them very frequently. Yes, it is certainly possible that some desirable organisms will be removed by such mechanical filtration, but I believe that the benefits of these "socks" far outweigh any disadvantages, as long as you pay attention to very frequent maintenance.>
3. Is 24 hour photoperiod still recommended? Noted FAQ that Anthony answered where he pointed out possible sexual crash, but then I also understand this is key to claim of keeping pH and oxygen levels more stable.
<I have employed a 24 hour cycle with macroalgae with good results, but a "reverse daylight" (i.e. light the macroalgae when the display is dark). In actuality, the "reverse" daylight technique is a more natural system; I don't think that keeping macroalgae in "stasis" is really  natural>
4. I see a some refugiums that don’t use the ‘Mud’. They sometimes also use live rock in the sump w or w/o the algae. In these cases, is the 24 hour photoperiod detrimental to the live rock?
<Well, it could be disruptive to the organisms which inhabit the rock, but the bacterial processes are probably unaffected.>
5. Are the bioballs that ecosystems recommends necessary? Will these become a maintenance issue down the road?
<I don't think that they will become problematic. From my understanding, these are actually used to keep debris from the macroalgae from escaping the sump.>
If you’ll indulge me on one more issue I’m struggling with: I’m trying to choose my aquarium size and have option of 18”, 24”, or 30” height. I like the look of the 30” height, but understand that it will drive the lighting requirements. I haven’t seen any quantitative numbers on this though. Is there a formula for determining difference in lighting level required to achieve same intensity as a function of water depth?
<Good question. I'm sure that there are certainly some highly scientific studies on this, and some applications of the inverse square law and other principles that can apply. However, I am a simple guy and I like to keep things well...simple. Here's my take on it: I tend to favor the 24" high tank, because you can still utilize 175 to 250 watt halides for most corals. In a 30" high tank, conventional wisdom is that you will need 400 watt halides. This is not "scientific"; merely based upon the work of hobbyists and personal experiences. Of course, there are many hardcore reefers who believe that you need such intense lights even in 14" tanks! I guess it all adds up to the fact that there are no right or wrong answers to every situation. You just need to assess the needs of your animals and take it from there!>
Thanks for your help. Bob.
<Glad to be of service, Bob! Regards, Scott F.>

Another DSB-LR-macroalgae-refugium question...
Hi there!
I have been reading through the WWM extensively for my project of starting a 90 gal reef tank. I have come a long way since I'm a beginner and am now fine-tuning my future set-up. Your feedback and answers are very important to me and I will not bypass any of your recommendations. Thanks in advance!  My questions and hesitations regard the refugium and the display tank DSB.  I'll start by explaining what I'm leaning to.  
There would be a 4" DSB of aragonite (CaribSea Aragamax Grand Bahama Reef Sand: 0.2-1.2mm with some shells and bigger bits) in the display tank. I'm planning to put a small LR rubble zone as well as a cup or two of Chaeto in the display tank to help keeping the display tank's DSB alive. I guess I'll put around 90 lbs of LR in the display. Now the fuge would be about 30 gal with a 6" DSB of sugar-fine aragonite, a 20lbs rubble of LR and some macro-algae (I'm interested in Chaeto or Thalassia or Gracilaria or Ulvales). There will be a Wave2K device in the display tank and there would be a 600 gal/hour of flow from/to sump-refugium (a Quiet-One pump).
<Mmm, a few things... if you can make the sump larger... I would... and do think about arranging the flow through the actual refugium part... to be less... what you have in mind pump, actual gallonage in flow, sump... will result in some thirty or so times turnover per hour... too much for the Chaeto, DSB>
The fuge will be on reverse schedule and I'm planning to skim only at night when the fuge's light is on and the display tank is dark. I think it's important to mention that I would eventually (after min. 6 months of waiting) get a mandarin in there (display tank, of course). I want to produce a lot of plankton in quantity and diversity. 
<It's obvious you've been doing your homework...>
Here are my too numerous questions (sorry...):
-After reading Dr. Shimek's article on setting up a DSB, I figured that the 0.2-1.2mm aragonite sand is lacking something. According to him, the DSB should include 40% of finer sand, that is between 0,06 and 0,12mm. Maybe it's not important enough to bother about it. Is it worth it or even useful to mix finer sand with the previously stated aragonite sand to get a better DSB?
<Is of greater utility, yes... in the longer haul, a year or more, of minimal consideration... finer sand will be made otherwise>
-For that matter should/could I mix some Biosediment from Kent of Mineral mud from CaribSea with the 0.2-1.2mm aragonite? If yes, do you have a preference for one of the two brands for the purpose of mixing it with aragonite sand?
<You could use this material... I wouldn't... in the present circumstance (flow rates) this material is going to be "blasted" all over the place... If you can arrange to segment off the refugium part of the sump for lower flow, or better, place another sump/refugium in parallel... this "mud" matter can be placed... again, something very much like it will accumulate in time... from your LR... mulm...>
-Regarding the macroalgae, I have eliminated the Halimeda because of competition with the corals for calcium and the Caulerpa for obvious reasons.  Now I'm hesitating between Chaeto, Thalassia, Gracilaria and Ulvales. Which one do you recommend best for my refugium?
<Actually, all... If you had to choose just one? The Chaetomorpha... but if you could combine them, I would do so>
Can I mix some of these? If not, can I mix them if there is one species in the display tank (let's say Chaeto) and another one in the fuge (maybe Thalassia or Ulva)? 
<Yes>
Maybe there is still a risk of chemical aggression and competition between the species when likewise "separated".
<Yes, definitely... it's "in the water">
-I read on WWM that the water flow to the fuge should be fairly slow for the plankton but very strong for the macro-algae. What do you recommend in my situation?
<Ahh!>
Is my flow rate (6X volume of display tank per hour, meaning 18X the volume of the fuge) a good compromise?
<Actually... the flow rate is a function of actual water volume (less than manufacturer estimate) per the REAL gallonage in your transit volume sump... this will NOT be 30 gallons... for one, the tank itself you will find is actually NOT thirty gallons (231 cubic inches in a gallon... go and measure), two, you won't be filling it all the way (as you will have a flood if/when the power or pump/s fail)... three, the contents of the tank (sand, rock, biota) displace some good part of the water volume... At any length, you will likely have less than ten gallons of actual water... My reason for encouraging you to upsize or add another sump>
-I would like the system to feed the corals with plankton and not almost exclusively sustain the mandarin. Would it be wiser to give up the mandarin then?
<Makes little difference... what goes in the Mandarin... will also help sustain your corals>
Can such a system feed both the mandarin and the corals (and maybe two other small non-sifting-fishes)?
<Yes>
Shimek insists a lot on NEVER putting a sand-sifting creature in a system with a DSB. I want the mandarin very much but if you say to forget it, I will. 
<Up to you... will add interest>
-Can I feed the fishes with macroalgae from the refugium? Not everybody seems to agree on that.
<You can>
-Will I still get some benefit from the trace elements present in the aragonite sand even tough I'm on a reverse schedule (pH will be more stable and aragonite won't dissolve?)?
<Yes>
-Are the macroalgae I mentioned likely to compete with the corals for nutrients?
<Yes, to extents>
-Do you know where on the net I could find more detailed summarized info about each of these algae species?
<Good question... no, I don't... but there is a HUGE amount of such data to sieve through in the scientific literature... and we have some articles on WWM re doing such searches>
Here are three other questions that are not related to our subject, if I may take the opportunity to ask:
-Is there a species of host-anemone that is not so risky to put in a reef tank?
<Captive produced Entacmaea quadricolor number one>
-Is it true that all LR that is not in full light are going to die?
<No... it might surprise you to know that live rock is actually a good deal buried in substrate in the wild... that the "live" part folks "turn up" is actually "upside down" in the wild... out of the sun for the most part.>
Some say to use base-rock at the bottom of the tank for that reason. I tough people were placing corals on the LV and that they would always be shaded anyway. Not sure to understand how to organize that.
-Is there a way of organizing a somehow similar "micro-fauna-autofeeding-system" in a freshwater tank?
<Yes... not commonly utilized in the U.S....>
I again apologize for the long e-mail. Many thanks!
Regards, Dominique Capelle
<Be chatting, Bob Fenner>

Re: A short follow up... Re: Another DSB-LR-macroalgae-refugium question...
Thanks for the quick and informative reply Mr. Fenner!
<Welcome>
So I will segment off a bigger fuge or place it in parallel (will discuss it with appliance person), reduce the flow with a valve, and mix a small amount of biosediment to the two DSBs.
<Ah, very good>
Now I still need to narrow down the choice of macroalgae I want in my system (fuge and display). I noticed that there somehow seems to be a friendly disagreement between you and Mr. Calfo about the use of macroalgae. 
<Yes... and many others of us here (WWM) and the aquarium spiel world at large...>
I remember some sentences from Anthony such as "please discipline yourself to use a single species of macroalgae... mixing is counterproductive... chemical aggressions...". Can you help me in my selection?
<Yes... and in an effort to be clear/er... there are many species of algae on reefs in the world... mostly delimited in size, dominance by predation rather than competition... Similarly, in captive systems of size there is little difficulty of chemical competition problems...>
As I said I'm interested in Chaetomorpha, Thalassia, Gracilaria and Ulvales. Are some combinations better (less competition and chemical aggressions)?
<Yes... per unit... grams of organism let's say, the vascular plants (e.g. Thalassia), reds (Gracilaria, Chaetomorpha) are less toxic/trouble than greens (Ulva) in this order>
My first concern is plankton production (don't know which one is better for that, best "epiphytic value"...).
<All in all, considering what conditions prevail in most marine aquariums, the reds are better here>
Of course, food source and nutrients export are also interesting "side-effects". Maybe it helps to mention I don't want to use
more than 2-3 watts per gallon in the refugium (maybe not enough for Thalassia). I'll have 5 watts per gallon in the display.
<The Thalassia has a much (likely an order of magnitude or less) rate of metabolism... it just doesn't "grow" compared to thallophytes... How to put this... we're back to the "argument" of whether to use more than one species... Which is what I would do... Will cc AnthonyC here for his (likely diverging) opinion... but I would place at least a macrophyte in addition to the embryophyte here... maybe one in the refugium, the other in the main tank>
Regarding this:
<<-Is there a way of organizing a somehow similar "micro-fauna-autofeeding-system" in a freshwater tank?
<Yes... not commonly utilized in the U.S....>
Is there information about it on the WWM, I didn't find any. If you had some reference (website or literature) it would sure be greatly appreciated.>>
<There are no popular works/hobbyist in English as far as I'm aware. I would pay a visit to a large/college library for more information>
Thank you so much!
Regards, Dominique Capelle, from Montreal (Canada)
P.S.: May I ask where you are located?
<I am in S. California (San Diego). Anthony resides in Pittsburgh, Penns. Bob Fenner>

Re: Another DSB-LR-macroalgae-refugium question...
Hi Mr. Fenner!
Nowhere else do I get such complete and detailed replies. So it shall be Thalassia and Gracilaria in my refugium as well as Chaeto in my display tank. Nice of you to have cc to Anthony. Will be interesting to have complementary points of view.
Am I right in saying that none of these (Thalassia, Gracilaria, and Chaeto) are likely to into a sexual repro phase?
Thanks!
Regards,
Dominique
<Seagrasses rarely "go to seed" under captive conditions... and algae... do reproduce by sporulation and sexually... but these genera, not a problem. Bob Fenner>

Macroalgae for the Refugium
Sorry to be a pain but I want to get my refugium set up right! I have some Halimeda growing in my display tank. It seems from reading your FAQ¹s that one species is recommend for a refugium. Is it alright, if I have the Halimeda in my display and something else in my refugium? (say Chaetomorpha or Gracilaria). 
<Yes, the Chaeto or Gracilaria will be fine John. James (Salty Dog)> 

Growing The "Good" Algae!
Dear Crew,
<Scott F. at your service tonight!>
Your web site is invaluable and very absorbing. One can make a career out of reading and pondering all the FAQs.
<Ain't that the truth!>
I will try to be succinct. I am very close to establishing a 210 gallon fish only marine aquarium. I also have a 26 gallon quarantine tank as part of the set up. My first question relates to algal growth. Although I do not envision a reef setup, I would like to grow coralline alga for aesthetic reasons. My tank dimensions are 72x24x30deep. Provided all other conditions are met, what is the minimum number of watts per gallon I will have to provide for adequate growth. Can I get by with less than
the 4-5 watts per gallon recommended for full-blown reef set ups?
<While a true "watt-per-gallon" figure is not all that telling, it seems like this would be sufficient to grow many coralline species, provided all of the other criteria for its growth are met.>
My second question has to do with macroalgae for nutrient export. I have a 50 gallon sump which will be filled with live rock as substrate for an algal turf. For reasons that you made clear, I intend to establish a monoculture and I would like to have your opinion as to the most desirable species to use. The criteria, would involve ease of maintenance and pleasing appearance. I will look forward for your reply. Sincerely,
Joe Steinberg
<Well, Joe, I'm inclined to recommend my favorite macroalgae, Chaetomorpha. It's an attractive and hardy algae, which can grow rapidly, and doesn't have the propensity to go "sexual" and release its gametes into the water, like Caulerpa species are prone to do. Also, it doesn't need to be anchored to rock like many other species. Since Chaetomorpha is easily harvested, it's an ideal macroalgae for nutrient export purposes. Do check it out and consider this awesome algae as your prime candidate for your system! Hope this helps! Regards, Scott F.>

Finalizing Skimmer Selection...
Ok, I've acquired a used 150g Oceanic Reef Ready tank, with a 29g sump and 29fuge. Between sump and fuge is a Little Giant 3mMDQX-SC to return with the Oceanic overflows/returns. I'll Plumb 1/2" pvc around the bottom under sand, with outlets coming out into 45 degree elbows on t's. I'm thinking 8 outlets centered around bottom from a Won Brothers Sen 900GA submerged hidden in rocks, but accessible if needed, eliminates 5ft of the head that way, instead of underneath tank. That's the idea for water movement.
<It certainly can work, but an internal pump may impart significant heat into the tank. A properly designed closed loop essentially operates with no real head pressure, and has the advantage of keeping the pump out of the tank. Just a thought.>
Dilemma: Trying to decide on skimmer, with looking over the FAQs and skimmer impression till I'm cross-eyed, Would the ASM G-3, extruded acrylic similar to Euro-reef 6-2, or the Ev120 being the 120 is $30 more than G-3, or the Ev180 that is $79 more. Of course that is even without the pumps for the Aqua C, would have to calculate a pump in that as well.
<I have seen and personally tested the G3 not too long ago, and find it to be an extremely capable, easy-to-operate skimmer. Based on the experience that I had, I would not hesitate to recommend it. It offers a lot of "bang for the buck", too!>
Also the on going expense to run the skimmer being considered. The ASM is a Sedra 5000 pump. Or would a My Reef Creations (local company) MR-1 with Sen900 pump being $250 plus about $80 for pump, The MR-1 is a Becket type, the DIY Anthony Calfo has on this site or Tunze Comline. Of course, something that I don't have to manipulate daily so it will skim would be appreciated. Granted don't mind the dumping of cup at daily feeding time.
<Gosh, all of the skimmers that you are considering are good models, offering value and performance. I'd go with the G3 based on it's simplicity.>
I have about 30" of height available, so shouldn't be a problem, person got it from had a EV120 on a box under the stand.  About 200Lbs LR overall. Skimmer and additional rock will be in sump side. I'll have to put a baffle on side with skimmer so that only the filthy water is skimmed, and output of skimmer on other side of baffle.
<Certainly can work.>
Rock and about a 10"dsb in 1 29g and acquire some Chaetomorpha (sp) Halimeda, and Chlorodesmis. Which would be best, a Combination of the 3?
<A combination is always nice, but I'm a big fan of Chaetomorpha, myself.>
Some Ulva Lettuce Plant-Aquacultured also in the fuge, harvested to feed tangs/angels. 65w pc light.  Plan on a A. Japonicus, Paracanthurus hepatus, Zebrasoma flavescens, Centropyge bispinosus, Couple Nemateleotris magnifica, 2 tank bred Amphiprion ocellaris, 1 Juvenile Pomacanthus imperator (until signs of getting stress in confines then trade with a club member that has larger system).
<I'd forgo the Emperor Angel altogether, unless you are ready to accommodate the fish for its entire life span.>
Lighting, Thinking 2T5 6500 from 9am-8pm and 2 Hamilton 175w 14k from 11a-3pm.
<Lighting scheme sounds fine for many animals; of course, you need to tailor the lighting for the animals that you intend to keep. Best of luck! Regards, Scott F.>

Regarding your advice
Hi there Bob, hopefully this email will get to YOU PERSONALLY. Just so you know, you have a great reputation in the Las Vegas Valley!!
<Man, I've got to get some of those nose, glasses and mustache disguises!>
Upon reading and reading to avoid having to bother you with an email, I stumbled across this in the WWM and I am now not 50% confused but 100%! lol! I have been researching adding macro-algae to my marine tank, and I have decided that Caulerpa is just too unstable and I don't want a 24-hour light on it. Anyhow, I have decided that the red kelp and several other NON-Caulerpa varieties are the way to go. Then I found an email where one of your guys, Anthony, said to an emailer to only pick ONE type of macro-algae as different kinds will fight (chemical warfare).
<Mmm, to some extent...>
Okay, but if it is all Grac., but different colors, isn't that okay. Does that mean I can't add shaving brush then? Does the kelp release toxins when they go asexual?
<Sort of release different chemicals all the time>
Or do any of the non-Caulerpa release toxin and cloud the tank when they go asexual?? 
<All life produces compounds that affect all other life... there, that's pretty much all-inclusive>
What can we mix?
<What you desire... some will "win out" over others depending on specifics of your situation... light, nutrients, et al... Bob Fenner> 

Macro algae distributors
Dear Bob
  I've bothered Anthony Calfo lately with too many questions so I thought I'd give him a break :)  
  Referencing the "Reef Invertebrate" book that Anthony and yourself wrote, I've been trying to find anyone  who sells macro algae like the pictures in your book (specifically page 71, the sample of Caulerpa, Ochtodes and Botryocladia).  I've found three different strains of Caulerpa but nothing on the two red species.
  Can you point me towards some links?  I'd really like to grow some of that red algae in my refugium.
Thanks for your time
  V/R
  J.J. Johanson
<I'd contact Morgan Lidster at Inland Aquatics (Terre Haute, Indiana) and Gerald Heslinga of Indo-Pacific Sea Farms (Big Island, HI) re. Bob Fenner>

Macro Algae...Which one? - 06/06/05
Dear Crew:
<<Greetings>>
I am looking for macro algae for my 29-gallon "suspension" refugium.  I built it specifically to allow water to flow from the bottom of the skimmer compartment upwards into the algae chamber.  The water then flows through a sieve and overflows into the return chamber where an Iwaki MD30RXT pumps it into a 75-gallon reef aquarium laden with live rock and oolithic sand.  Hopefully, the flow can keep macro algae suspended and tumbling in the refugium.
Currently, the refugium is bare with no live rock or sand to serve as algal anchors.
<<I like to put a deep sand bed here.>>
Each weekend, I perform a 25-gallon water change to supplement the efforts of my Remora skimmer and to keep my anemones, coral and fish thriving.  I want the macro algae to reduce the need for massive water changes and to out-compete diatoms since my Kold Ster-il unit does not filter silica.
<<I'm not aware of macro algae doing much of anything for silicates.  But adding it for nutrient export is still a great idea.>>
Is there any consensus regarding the "best" macro algae for my needs?  I originally had Gracilaria parvispora in mind but there are postings to indicate that it does not do well in a nutrient-poor environment required to prevent diatom outbreaks.
<<My vote would be to add Chaetomorpha linum for nutrient export...and not sweat the silicates.  Diatoms usually show as part of the natural algae progression during a tank cycle, but subsequent outbreaks are usually easily controlled with adequate water flow in the system.  Silicates are best controlled by water filtration.  If you don't have a diatom problem now, the fact that you are doing such large water changes as often as you are would suggest that you don't have much (if indeed any) of a silicate problem with your make-up water.>>
Regards, Paul.
<<Eric R.>>

Refugium question
Aloha Mr. Fenner,
mike here, i had a question about live refugium starter kits. i currently have a 30 gallon reef system with a 15 gallon refugium/sump.
my tank has been up for about 2 yrs now.  my only filtration is a small Penguin Biowheel filter and a Seaclone 150, it seems to be doing an alright job.
<Fine for this size system, with good care/maintenance overall>
(i was going to pick up a Georeef skimmer cs6-1, i also wanted your opinion about overskimming).
<No need to switch here>
the starter kit i was interested in was the inland aquatics flora and fauna kits. they can be
found here http://www.inlandaquatics.com/prod/prod_refu.html .
<Ah, yes. Know the owner/manager, Morgan Lidster. A fine fellow>
would you suggest using this product to boost ones refugium?
<Yes>
do you have other suggestions for a more natural type of biological filtration?
<Mmm, the periodic trading out of substrates (rock, sand...). Not easily done in Hawai'i.>
I'm afraid the types of algae included in the kit may try to reproduce and cause my tank to crash (the Caulerpa algae mainly). i have already spoken to the personnel at inland but i just wanted a second opinion.
your opinion and suggestions are greatly appreciated.
Aloha
mike
<Considering your success, apparent good care, powers of observation... I would not be concerned re one type of algae over-populating this bit of water. Keep trimming it and you'll be fine. Bob Fenner>

Reef Aquarium Set-up 7/30/05
Hi there!
<<Hello - Ted here>>
I'd firstly like to congratulate you on a site that is packed full of information - reading through some of it has finally given me the inspiration I needed to set up a larger marine tank of my own - its awesome! :)<<Thanks for the feedback.>>
So, I'm currently in the process of setting up a 60 gallon tank, with a 20 gallon sump, incorporating 3 sections - refugium, skimmer and return.
My first question is about the cycling process for a refugium setup. I have cycled a tank with plastic biomedia before and fully understand the cycling process - is the cycling process exactly the same for refugium setup? i.e. drop in a few shrimps, and away you go?
<<The cycling process is identical.>>
To kickoff the cycle, what would you think about just stocking it full with about 20 kg.s of uncured live rock?? <<Cycling a system with live rock is good method.>> Will it start getting a bit messy and require way too many water changes?<<How messy and how many water changes would depend. How fresh is the live rock? The less time the live rock is out of water, the better the chances that organisms will survive the relocation to you new setup. Decaying material in the live rock feeds the cycle and the more decaying matter, the stronger the odor of decay and the more water changes.>>
One last question - I live in Australia, and am finding it almost impossible to get hold of any Chaetomorpha for my fuge - is this species of macroalgae unique to certain areas or should it exist on all coral reefs?<<There are several species of Chaetomorpha. The one most commonly found in home reef systems in C. linum. It is also called spaghetti algae>>
If I still have no success obtaining Chaetomorpha, what is your opinion on Caulerpa?? How high is the risk of it going sexual and leaching nutrients back into the wate?<<If the goal is nutrient export, then I would use Chaetomorpha. It does not have the issues that Caulerpa does.
Caulerpa can go sexual with excessive growth or changes in lighting. It is simpler to use Chaetomorpha. Many successful systems use Caulerpa so if you can't find Chaetomorpha anywhere, go ahead and use Caulerpa.>>
Thank you so much for your time.
<<You're welcome!>>
Paul
<<Cheers - Ted>>

Macro-Algae Choices for Marine Refugiums  10/20/05
Hi Crew!
<Hi Steven.>
Another question (hopefully I am not boring anyone).
<What I’m sorry I was dozing off, just teasing. No worries.>
I read the FAQ sections regarding Caulerpa and the movement towards banning of it. <Already banned in my state, irresponsible discarding is to blame.> I have had some growing in my refugium section of my wet/dry for about a month now.  It was placed on top of crushed live rock and I have
mini PC lights on it 24 hours. <Good be sure to prune it, keep it in check and avoid a “sexual” event.>  I have also read about most of the "Crew" really liking Red Gracilaria much better.  <Yes but it is very difficult to grow, Chaetomorpha is a good alternative.> My question is does either of these two work any better in a refugium, (i.e. controlling nitrates, natural filtration, fortification, etc.)? <Grac. Would be better…if you could get it to grow, most can’t.>  How long does a refugium need to be established before recognizing the benefits?
<Varies from system to system but a few months in my experience before noticing drastic changes.>
  Can I place both plants in the refugium?
<No, one will “strangle” the other in competition.>
In addition, I have read that both of these are beneficial to Tangs if offered to graze on periodically. <Yes tangs are herbivores.>  Are either of the two better suited for this?
<In my experience tangs definitely prefer the Grac.>
Thank you so much for helping us "novices trying to do the right thing" from making wrong decisions.
<Your welcome.>
Regards, Steven  
<Adam J.>