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FAQs on Marine Algae Eaters as Controls 1

Related FAQs: Marine Algae Eaters 2, Scavengers/Clean-up Crews for Marine Aquariums, by Bob Fenner, Some Fishes Are Good For More Than Just Looking At, by James Fatherree, Algae ControlMarine Algicide Use, Nutrient Limitation, Culturing Macro-Algae; Controlling: BGA/Cyano, Red/Encrusting Algae, Green Algae, Brown/Diatom AlgaeSnail Selection, Snail Compatibility,

Related Articles: Algae-eating ("Lawnmower") Blennies of the Genera Salarias & Atrosalarias, Algae Control, Marine Maintenance, Nutrient Control and Export, Marine Scavengers, Snails, Hermit Crabs, Mithrax/Emerald Green Crabs, Sea Urchins, Blennies,   Algae-eating Blennies of the Genera Salarias & Atrosalarias, 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 Algae Filters,

Lawn Mower Blenny

New Print and eBook on Amazon

Marine Aquarium Algae Control

by Robert (Bob) Fenner

Elysia viridis. Looking For A Bryopsis Grazer - 05/06/07 Good Morning all, <<Greetings>> I have been working on a Bryopsis problem for a while now and have been doing regular water changes to combat the situation. <<Have you looked through our info re nuisance algae?  Raising your system's pH to 8.5/8.6 and keeping it there for several weeks has shown anecdotal proof of helping to eliminate this pest alga>> My battle has lead me to research additional means. <<Ah...ok>> I have found that a sea slug of the order Sacoglossa, Elysia viridis, has made claims to eat Bryopsis exclusively. <<Mmm, not "exclusively"...at least not according to seaslugforum.net>> The problem I am having is finding this slug in stores? <<I think this animal is more a cool/temperate species than a tropical species, based on its distribution in the Northeast Atlantic>> I have been told my LFS that the Lettuce Sea Slug is the same thing as the Viridis, however I am not sure if they are. <<Elysia crispata (Lettuce Sea Slug) is a distinctly different species from E. viridis hailing from different locales...and quite apparent when viewed>> I know they are of the same family but not the same species? <<Correct>> Can you help me decided on whether or not to buy a Lettuce Sea Slug for my battle, or if not, where I can obtain an Elysia Viridis? <<I would NOT buy the Lettuce Sea Slug.  Little is known of what these animals really eat (even though they are actively marketed/sold as grazers of "hair algae").  Many of these slugs are able to harbor the living chloroplasts of the algae they consume which continue to photosynthesize within the body of the sea slug, providing it with sugars for its own nutrition.  E. crispata have been found to contain the ingested symbiotic plastids from Halimeda incrassata and Penicillus capitatus...hardly "hair" algae.  My own anecdotal observations and experiences would seem to bear this out as I have never known one survive more than a few weeks to months in a home aquarist's system, even with an abundance of hair algae present, as they all seem to ultimately shrink and die from starvation.  I think a better choice of slug to try would be from the genus Aplysia...the Sea Hares.  These slugs; at least in my opinion/experience, are more hardy and much more likely to consume the filamentous algae than E. crispata>>   Thank You for Your Time <<Happy to share.  EricR>>

Algae Control/Snails   3/18/06 I tried searching, and I am sure it is there somewhere, but there is so much infor to retain.  What type of snails control algae and also, how many should I have in a 72 gallon tank?  <Turbo and Astrea snails are good choices.  The amount needed is relevant to the size of the snails and amount of algae you need to control.  In your tank I would go with five or six of each.  <James (Salty Dog)> Thanks!  <You're welcome>

What Will Munch Caulerpa? 8/17/05 Hello Bob, <Actually, Scott F. in tonight!> First of all, I'd like to say I appreciate your site and am thankful for the help you've given me in the past. I try doing the research myself as I realize your time is valuable.  That said, I've read the algae control FAQ's and the Algae ID'S.  The algae ID section noted that Razor Caulerpa was very hard to get rid of and not very palatable to most fish. <That's correct. Many fishes will not touch it.> So I read the algae control FAQ'S and didn't find Razor Caulerpa specific questions (most just read algae).  I did read that lawn mower blennies do a great job of controlling algae but I wasn't sure if that applied to razor Caulerpa. <Not in my experience. It's simply too tough for these guys. In fact, I think that the Lawnmower Blenny is highly overrated as an algae eater...A great fish with a fun personality, but not all that great at consuming algae, IMO.> So my question is, "What will eat the Razor Caulerpa?"  I have a 55 gallon tank with a hydor20 canister filter and a power head for water circulation.  There is no media in the canister filter. I top my water off with water from my planted discus tank (remember that question?) and have some mangroves in lieu of protein skimmers and about 4" on aragonite #00 and 50 lbs of live rock.  For lighting, I have two 65 watt 50/50 Power compacts.  I've never had anything die on me except an octopus after about four months.  The water is very clear and everyone seems happy except me because of Razor Caulerpa, which I fear will overtake my tank.  I have about 20 Blue Mushrooms, a Blue Sponge, 1 large Yellow Gorgonian, Sun Polyps (they've released spores that matured into little Sun Polyps throughout the tank), a small Orange Starfish covered in what appears to be orange thorns (not sure what kind it is), a mated pair of False Percula Clowns, a Mandarin Dragonet, and a Pajama Cardinal.  Everyone except the Mandarin (I've seen him eat formula 1 in addition to the pods all over the glass) has been in the tank for over a year.  The only mineral supplementing I do is adding one of those little white cubes whenever one runs out which is about every two weeks.  I scrape lots of red and green coralline algae of my glass weekly.  Back to my question, what will help with my Razor Caulerpa problem?  Any advice is much appreciated.  Thank You. <Well, short of manual extraction, there are not a ton of fishes that will eat the stuff. Some Zebrasoma Tangs will do the job, but you need to have a system that suits the Tang's long term needs. And, Tangs are individuals; some may never touch any Caulerpa at all! You just cannot be certain. I'm afraid that manual extraction is the best bet in dealing with this algae.> p.s. I did have a Moorish Idol die on me, but it wasn't my fault.  I casually told my wife I'd love to get one someday and one day I came home to see a Moorish idol lying on its side.  She bought it for me while I was at work and it was dead a half hour after I got home. I wanted to yell at her because I've advised her against buying stuff without proper research on my part many times but her smile at the thought of the wonderful surprise she thought she was giving me overcame the urge to yell.  Still it was very sad to think the Moorish Idol was pulled from the ocean to die in my tank.  I think she learned her lesson from that (we lucked out on the orange starfish being harmless so far, that was her surprise also).  auughhh <Well, it is certainly a tragedy that these fishes are available to the causal hobbyist, but here intentions were certainly good. I guess we all need to educate our spouses and significant others on the suitability of some animals for captive life, and the unsuitability of others. It's a good practice for us, for the environment, and for the hobby. Best of luck! Regards, Scott F.>

Electric Orange Hermit Crabs 08/09/03 <Hi Steve, PF with you today.> I searched all over the web and on your WONDERFUL webpage but found no information on what I was looking for.  I have a green hair algae problem right now that I am in the middle of fixing.  At this point I think I just need a few extra cleaners in my tank to finish the job.  I was wondering how you felt about the Electric Orange Hermit Crabs (Aniculus sp.). <Well, after reading on ahead, I'd say stick with the hermits you already have and give it time. One way to remove the hair algae would be to use a dedicated (i.e. don't use it for anything else, ever) toothbrush and lightly scrub the rock during your water change. Use the siphon to vacuum out the algae. Have you looked at your water parameters? It could be a nitrate or phosphate problem causing the growth. The algae needs to get food from somewhere in order to grow.> Am I better off getting scarlet hermits, or is their even a better creature for me to help out with my hair algae?  I have a 29 gallon tank with one flame angel, one percula clown, and one Sleeper Gold Head Goby (not very old).  I might give away the Goby if I don't upgrade to a larger tank within a year. I have 2 scarlet hermits, 2 blue legged hermits, and 2 red legged hermits.  I also have 4 Nerites snails.  So, any suggestions on what hermit (or any other creature) to buy that likes to eat hair algae would be great! Thanks, and keep up the great work on your website. Steve <Test your water first, as I said above, and give your critters time to work, nothing good ever happens fast in a reef tank, in the woods of a very wise friend of mine. Have a good day, and let us know how it turns out. PF>

-It doesn't pay to sample a Nudi!- I feel that I know the answer to this but, we just purchased a lettuce nudibranch and noticed that he had been nipped.  The second day there was a little piece of him on the substrate but he was still moving along just fine.  By the evening our Sailfin tang was dead and by the next morning our very large yellow tang was also dead. <The two most interested in an algae meal...>  My assumption is that these are the two fish that nipped at the nudibranch. <Likely, the thing does look like a tasty clump of algae.> I have removed our new addition.  Is there anything I need to do other than a water change to help protect the other fish? <I would add new/replace activated carbon in the tank and do a small water change for good measure.>  As I mentioned, the nudibranch was still alive. Thanks for your help. <Good luck! -Kevin> KatMcD

- Snails: No Good for Algae Control? - Dear Bob: <Kevin here> Hello Bob, my name is Keith, I have read your book and many others on saltwater. My problem is there is all this talk about more biology and less technology, but I haven't seen the biology part. <ok...> I have been fighting algae for 2 years and was about ready to give up. I acquired all the technology, but the algae fight was ongoing. then by word of mouth of another aquarist, I bought a Kole Tang 2 days  ago, and diatoms are being biologically ate out of my tank with the help on the algae side by a yellow tang. All this talk of snails, RO/DI which I am using, protein skimming, which is in use, are mostly Technical not biological. <Well, that's arguable; protein skimming is very much a natural process, snails are definitely a biological means of algae control, and we're only supposed to be adding purified water to our tanks anyway.> All Snails do is fall on their  backs and die. <Sounds like an acclimation issue, the fault of hermit crabs, or the unfortunate shell shape of the Caribbean Astrea snails. Snails are very efficient little micro algae controllers.> And all the people selling them in pet stores as a cure for algae and diatoms should be shot. <Well, that wouldn't leave many people in the marine aquarium industry, now, would it? Snails should not be looked at as a "cure" to an algae problem, but as a part of the solution. Algae problems are solved by limiting the incoming nutrients, using the proper lighting, and applying appropriate herbivores. There is no rocket science to algae control. Check out all wetweb has to offer about algae control and the gazillions of FAQ's on the same subject.  Good luck! -Kevin> Sincerely Keith

Algae control Help: I have Turtle weed (a little bit) and bristle ball brush (lots) what inverts would be the best route. I have a 20 gal long mini reef w/ 55 watts compact actinic and 15 watts white standard flo. light. I have a prism pro, 2 powerheads in front, a 170 bio wheel, 40 lbs live sand, about 30 lbs live rock and various soft corals. The corals are doing great but so is the algae, I leave my lights on for 12 hours a day. I have a few Astrea snails, and red leg hermits. What should I add to kill the algae?<would purchase a clean up crew...maybe from liveaquaria.com (they have some good ones!) also I would check all the water parameters (phosphates, etc) and check the water you use. if you use tap water I would switch to Reverse Osmosis water> Do all urchins eat coralline algae?<They will eat anything and everything got this from the link) http://www.wetwebmedia.com/urchins.htm > Thanks!!!<IanB> Adam

Live rock covered in a black plague! Aloha WWM Crew, Thanks for the wonderful service you provide. <Happy to be of help!>  I have a 55 gallon FOWLR that's been running for about 9 months.  Over the past couple months I noticed numerous black spots on the live rock.  Some of the patches are getting to be about 1" in diameter.  When I scrape it off the rocks it seems to spread even quicker. <Ew>  What is this stuff? <Most likely an algae of some sort> It is black or a very dark green algae and only appears on the rocks.  One of the rocks is completely covered with the black stuff.  I have scrubbed that rock with a toothbrush, but it comes back thicker.   Please help.   <I have no clue what kind of algae that is. I'd pick up a diadema urchin; if it's an algae, the urchin will go to town on it. Make sure it gets enough to eat though, I just watched mine munch a path through an encrusting Montipora! Try some big snails, the diadema urchin, and even a lawnmower/algae blenny if you do not have really aggressive fish and/or crustacean eaters. Also make sure that you are using water purified by either reverse osmosis or deionization (or both) and that there is no detectable phosphate in your tank water. You may also wish to add some macroalgae such as Caulerpa to help steal nutrients away from this plague stuff. Also (boy am I getting long winded!) make sure that your protein skimmer is functioning correctly, that you have one of adequate size for your aquarium, and that you... well... have one, I'd strongly recommend it. Hope this is of some help, maybe take some pictures. -Kevin> Mahalo, Jeff Mithrax Crabs    Hey fellers, <Hey Hey> I was just reading your postings on bubble algae. I have a small patch of the stuff which I vacuumed up once but it came right back. I saw your recommendation for Mithrax crabs.  Are they reef safe? <They are supposed to be, but every crab has its own personality.> Do they have a common name or are they only known as Mithrax crabs?    <Around here (Northern California) they are usually labeled Emerald or Green Crabs.> One last; could aging lights be partially responsible for this pesky stuff?  I've never had troublesome algae before. <Can happen with other types of nuisance algae, but not usually the bubble algae.  As the bulbs get older they can drift towards the warmer end of the spectrum and encourage nuisance algae.  Be sure nutrient export is good, manual removal of the algae may work best. -Gage>

Question on sea urchin diet Hi again, I was told by the lps that a pencil urchin which i already bought only eats algae and sometimes coralline algae. <neither is true at all... although more urchins than not do eat microalgae nicely. The pencil urchin is too often sold for algae control and it starves instead in most aquaria... it has decided carnivorous inclinations. Eating thawed meaty foods and sinking pellets is much better for it> Today i woke up to enjoy my tank and too my horror my urchin was eating my starfish leg?! Is that normal hope he doesn't die seeing as the star fish was 19.99 and the pencil urchin was 6.99. <although I'm a bit "put off" by your valuation of creature's lives in relation to how much money you've spent on them, I can tell you that the urchin did not attack and kill your starfish... the urchin is merely a meaty scavenger. Your starfish aborted a leg or is dying for another reason altogether. If the starfish is new and/or has not been quarantined then you may have your answer already>> will the urchin do this to my mushrooms and polyps? <not likely... and please be sure to research these animals needs in advance of a purchase. Merely taking the word of a clerk that is trying to sell you something is not your best route as a consumer.> I hope not anyways tell me what you think so i can get rid of it. thanks JM <wow... please do browse the archives... and consider getting a good book or two to keep on hand. Mike Paletta "New Marine Aquarium" is a good start. Fenner's :Conscientious Marine Aquarist" will put you on an even better track. Borneman for corals ("Aquarium Corals"). Best regards, Anthony>

Algae ID/Sailfin tang 4/2/03 Anthony, A greeting from Denver! <cheers, my friend> Well you're right, that Bryopsis is still a problem that won't go away. <indeed tough... not strictly limited by nutrients. Have to tried the elevated pH? A consistently high ph (about 8.6) and high Redox over time help to discourage this algae> I do weekly water changes of 15-20 gallons (out of a 70 gal) with Reef crystals by Aquarium Systems, have a Remora Pro, at least 650 GPH water thru filter, lots of carbon and still a nutrient problem of some sort. When the Bryopsis is very apparent on the crushed coral I pull it out with any CC still attached, last time I just netted a top layer of the substrate out going to eventually keep doing that until there's only about an inch of CC left (crushed coral holds nutrients I hear). The "plant" seen in the pictures is very cool & I don't want to lose it, the lettuce Nudi did eat some of the Bryopsis, but, it must have died as I can't find it now. Do you suppose a Sailfin or chevron tang might eat the Bryopsis, yet leave the "plant"? <very much so. And the "plant" BTW is looking more and more like Sargassum> I have a couple of other questions for ya concerning a possible conflict between corals, but, I'll send that one separately with pics. (Just another excuse to  chat with ya!) Thanks, your friend in Denver-Scott <best regards! Anthony>

What fish eat algae We have a 37 gallon tank with 1 neon Dottyback 1 blue damsels 1 tomato clown 1 pink tipped anemone What could we put into the tank to eat algae.  We thought about a tang but there isn't enough space now.  Is there any small fish that would work? >>I can't think of anything other than a Lawnmower blenny, or going with an invert such as a tropical abalone, but I would worry that the abalone might not find enough to eat in such a small tank.  Otherwise, I will suggest testing your water parameters, including for phosphates, and decide if nutrient export could be the problem. >Will the clown ever go to the anemone? >>This is part of the trouble with clowns, there is no guarantee that they'll host, or WHAT they'll host.  I've heard of them hosting everything from powerheads to overflows.  Look here for info on the pink tip--> http://www.wetwebmedia.com/marine/inverts/cnidaria/anthozoa/anemones.htm and here--> http://www.wetwebmedia.com/marine/inverts/cnidaria/anthozoa/anemoneselfaqs.htm Marina Ken Swanson

- Who Eats this Stuff? - <Hello, JasonC here...> i picked up  4 emerald green crabs and 15 ultra tiny hermit crabs, and 30 turbo snails. I have a 55 gallon reef tank with mostly live rock, polyps and some SPS coral. but hair algae, Bryopsis & Vilonia (spelling) algaes as main problem. < http://www.wetwebmedia.com/greenalg.htm > I heard that only the emerald green crabs eat the Valonia bubble algae. <Emerald crabs will eat Valonia, but they will also learn to eat other things like small fish. Cheers, J -- >

Hermit crabs - algae Dear WWM: If you were to choose 5 species of hermit crab or crabs in general, for routine cleanup of green hair and filamentous algae in my reef tank, which would they be? I intend on having corals and want "reef safe" varieties. I live in Ft. Lauderdale and can collect hermits from the tide pools.  Can I use these?  If so, what species...blue legged, red legged, etc Thanks, Steve < I would do mainly red leg hermits.  Sally lightfoots are good at eating hair algae also. Cody>

Attacking Algae With Snails! Greetings and Salutations: <Good afternoon- Scott F. here for you!> I have a 55gal FOWLR (with an eye towards inverts), and a covering of green algae on the glass and substrate.  I'd like 1-2 snails and 1-2 crabs (that stay small) to help out a little.  Which species would you suggest specifically?  I do not want too many or too big of anything, and I expect that they won't solve the problem entirely, just that they pitch in "for the cause". Thanks. <I like to use Strombus, Trochus, and sometimes, Nerita snails. They all do a pretty good job on different types of algae, and many will reproduce readily, so you can share 'em with your friends! Hope this helps.  Scott>

Feeding Tangs Thank you very much for your prompt answer, now I'm sure it is a Chrysiptera parasema. Another question...With the damsels I bought a Tang (Zebrasoma ). It attacked all the green hair algae. If he (or she) is still eating at that rate, my tank will be free of green hair algae in just a few days more... my question is: Then, what am I going to give him (or her) to eat? <Please look at the writings on WWM concerning Surgeonfishes. -Steven Pro>

Re: Clean up crew Why an abalone? They are very expensive. I purchased one and have been reading up on them, but I was just wondering why you suggested this animal. <they are AMAZING and incomparable herbivores once established>

Re: Tang Sorry about the misc. other fish. I meant to include the word "small." <no worries, bud <smile>> The fish I have right now are two blue damsels, two Percula clowns, a lawnmower blenny, and a royal gramma (also the angel). My primary interest for the tang was for control of a filamentous green algae. Three further questions: Even though a tang would not be very good in the tank, which tang (from below or otherwise) would you consider to be the "best" for algae control in the 40 gallon? <yellow eye tangs are best at cropping algae very low/squeaky clean. Zebrasomas just nip and tear. None eat long algae well at all (must be cropped for them first)> What other fish would you recommend for filamentous algae control? <Foxface/rabbitfish are also quite good (although venomous). Generally peaceful too> Are there any inverts other than the usual snails and a variety of hermit crabs that would help control the algae? <tropical abalone are outstanding!!! Available from Tonga cultured. See if your LFS or online supplier gets Tonga stock> Thanks, Kevin Cossel <best regards, Anthony>

Algae Time Greetings again Robert. I hope that you are keeping well. <Steven Pro this morning and I am quite fine.> I have a number of questions that I need your help with. I have had the 100 gallon tank up and running for about 4 months now and again seem to be going through the noxious red and hair algae. I am getting really annoyed as I cannot get rid of it. The Scopas tang wants nothing to do with it and the hermits crabs are ignoring it as well. <Very normal for these animals to not eat these undesirable algae.> Here are the specs again. 100Gal, 4 power compact fluorescents, Eheim pro wet dry canister filter, 250 GPH protein skimmer sea clone. <Are you getting good production from your skimmer?> Nitrate 0 ammonia .25, nitrite 0, calcium 410, phosphates 0, 14 DKH, PH 8.3 I dose with Iodine, and Kalkwasser. Nothing seems to be helping the algae problem. What would you recommend? <Aggressive skimming, careful feeding and stocking, and use of purified water.> Is my protein skimmer to weak for this tank, and if so what should I get to replace it. <Probably. Take a quick read through the WWM site on skimmer selection for various brand recommendations.> Also ever since the algae has been growing the feather dusters spend most of their time withdrawn, and the Sand anemone and long tip anemone are also spending the majority of their time curled into balls. I also have my still sick xenia and a Goniopora. Could the algae be causing this. <Maybe causing or a symptom of other problems.> I need your advice. I have been considering moving the anemones and the corals to my smaller 30 gallon and seeing if they cheered up. <Far better and less stressful to keep them in their current tank with the lighting they have adapted to and to remedy the underlying cause for the prolific algae. Do read through the files and FAQ's are algae control, too.> Fish are, a scopas tang, 2 percs, 1 scooter dragonet and 2 cleaner shrimp. <Not overstocked at all.> All the vertebrates seem quite happy and eat well. Let me know if you have any suggestions as I am tired of my wonderful aquarium looking like a swamp. <Have a faith and patience and I am sure you can correct the problem.> Best regards. Julian Hunt <Have a nice day. -Steven Pro>

Algae Cleaners Hi, quick question. I have an aggressive setup with a Picasso trigger, panther grouper, Foxface, 3 striped damsel and soon a Koran angel. What are my options for something to help with the algae without becoming food? Thanks again... Tim <Extremely limited with the Picasso, no inverts. The Foxface and Koran Angel should be helping. A large Tang might help too. Avoid a Yellow, as he and the Foxface will probably fight a lot. Also, water changes, aggressive protein skimming, perhaps a algal filter, etc. for nutrient export. -Steven Pro>

Need A Mower for my Hair Algae  Hey Bob, <<JasonC here - Bob has gone diving.>> I have green hair algae that just won't go away. I kinda know why so I would like to know a way to get it in balance. The Tank is just under a year old. Actually let me back up and tell ya why I believe I have algae..... I use Seachem Amino's.... this product keeps my corals looking amazing.... BUT it does promote algae.... this I already know.... So I have 2 Lawn Mover Blennies... they actually never stop eating (the glass never has brown algae any more) but they wont eat the longer stuff (even when I attempt to try and make it fresher by trimming it). I have 3 tangs (yellow, purple, hippo) had tried a Kole tang twice but they died within 10 days each.... Dunno why? <<perhaps some shipping related thing. Do you quarantine you in-comers?>> Never found one of them either. Now that I have more experience I am also aware that my tank would not be big enough (in the future) to support all these Tangs. OK some stats.... 110 Gallon reef, 173lbs LR, 160lbs crushed coral substrate, about a dozen of the common reef tank type corals, shrimps etc. about 100 crabs and 60 snails.... some crabs are actually getting too big..( one we call White Claw, he now inhabits a GIANT Turbo snail shell) <<large crabs are not to be trusted.>> Additives I use are all Seachem except the RO/DI additive from Kent. I use CA, Reef Buffer, Reef Builder and Iodine dats it... Only use RO/DI which I bought for the algae mostly... no diff after about 6 big water changes.... I know life is flourishing in my tank that is for sure... I am getting new stuff growing in there all the time... my Hard plate coral has grown a centimeter in just 7 weeks. I have tons of those little pod creatures.... when I remove algae there are always a few that go with :) Looks like I will finally get a chance to try a Mandarin Goby :) <<need to deal with the algae first>> Don't really know if the very last thing "I" can think of will help... That would be refugium... don't really feel like making one anymore :) Since there are so many hiding places in the main tank it would only be for macro algae and PH stability... (which I cant get over 8.2 btw... falls as low as 7.9 at night.... is that an acceptable drop? <<I would go the refugium route, and in fact is what I am doing personally do handle the same problem in my fish-only. Need something to compete with it... and also pull as much out as you can with your hands.>> Ok this mail is wayyyyy too long... Thanks for your advice, Kind regards, Robert <<No problem, good luck with the algae. Cheers, J -- >>

A Question of Algae Eating Inverts Dear Robert, <You reached Steven pro today, filling in for Bob.> Thank you for answering my last question. I now have another question. I have hair algae problem, in my 29 gallon tank, can I put red legged hermits with my live rock? Will they destroy my rock? <Scarlet red reef hermit crabs are one of my favorites. They are pretty much strictly algae and detritus feeders. I have never had any problems with these, unlike the blue legged hermit crabs.> I do have a sally light foot crab and was thinking that I should put an emerald crab to help control the hair algae. I know that it is a possibility that they will fight or kill each other, but is this usually the case. <Hard to say for sure. That is why there is a difference in the articles you have read. I would probably advise against both in a 29. Less room for one to get away.> In some articles that I read says that they have different habits and don't usually bother each other. My tank has plenty of hiding places and live sand if that helps any. I do want some more inverts in my tank, what is the route that you would take in my situation. I won't hold you responsible for any decisions that I make, so please give any advice or info that you have. Thanks <I hope I have been helpful. In recap, Scarlets yes, emerald no. -Steven Pro>

Emerald Green crab attacks! Hi Bob, I just got back from my favorite fish shops in Chicagoland. Realized I really do have more time than money. Any way, I saw something there I could not believe. I watched an Emerald crab reach out and snag a Saddlebacked Clownfish.  <This does happen... with size, hunger, Mithrax crabs will eat most anything> It grabbed him and drug him down and held the poor thing fast while it started to try to eat it! I quickly got an employee and its life was spared. (maybe) Is this normal or just a case a very hungry crab? I was thinking about picking up a few until that event. Thanks for your input on the lights. I just purchased the CSL ABS 4-65 watt Power Compact unit online. I also decided to buy a 75Ga. and sell the 55Ga. More room (width) for the lights, filters, livestock etc.. Just plain easier all the way around is you ask me. Oh, buy the way, do you need a 55Ga. tank. I know someone who is selling. <Do post this on the Chatforum: http://talk.wetwebfotos.com/ Bob Fenner> Thanks Zimmy

Bubble Algae Any suggestions as to elimination other than removing each piece of live rock and cleaning? I have a single Mithrax crab for a 55 gallon with 50 pounds of live rock. Also have Berlin skimmer, 15W UV, Fluval 404. System is 26 months old and this stuff has just shown up in the last two weeks. <This information stored on our principal site, starting here: http://www.wetwebmedia.com/algaeconMar.htm Bob Fenner> Thanks Jim Nix

invertebrates for red / green algae Thank you for helping me find out what kind of algae I had in my tank the information helped a lot. Sorry to bother you with another question, a lot of people have said that crabs and could you give me some other invertebrates that would help with red and green algae. thank you don <Please read over the sections on our site re algae control. Perhaps starting here: http://www.wetwebmedia.com/algaeconMar.htm Bob Fenner>

Tridachia diomedea - feeding Bob, FFExpress sells this nudibranch - it is partially photosynthetic and apparently eats algae. I'm interested in obtaining one/some, if its likely to survive in a reef tank and had some questions for you: 1) Would you recommend this as a hardy nudibranch (75 gal reef tank, 100 lbs of fiji LR, lots of macro algae (in tank and sump-refugium). <For trying out as an algae eater? Not really... there are fishes that are superior. Please read: http://www.wetwebmedia.com/algeatrcontfaqs.htm As a species, specimen to try? Sure> 2) What specific types of algae does it eat <Mostly "soft" greens (chlorophytes), some reds (rhodophytes)> 3) Would lysmata shrimp (fire and peppermint) eat it? <Unlikely> 4) would it harm corals (leathers, sps, lps, mushrooms, anemones). <Very unlikely> I searched the web, but couldn't find much info on this nudi - in terms of suitability in a reef tank - although ffexpress had some faqs that made it sound like a relatively hardy animal. <Have heard mixed results of using these naked gill slugs in captivity. Either positive or "just dissolved" (though not toxic), as with many nudibranchs. Do consider using an algae-eating blenny, Ctenochaetus tang, investigating the root causes of algal problems... Bob Fenner> Thanks!

need a recommendation (marine algae eater) Hello Bob, when you made this recommendation: Can you recommend something I can add to my tank to eat this algae. <My fave choice for first try: a Salarias fasciatus: did you mean this: Jeweled Blenny ? <Please read about this fish on our site: www.WetWebMedia.com> Also, I read on your site about protein skimmers. I am looking for something in between a SeaClone and a AquaC EV90. I have been told to get a SeaClone, but I read it has it's problems. You recommend the AquaC EV, but it's about $300. is there something between the $70.00 SeaClone and the $300.00 AquaC? <All sorts... again read the site... on Skimmer Selection FAQs> I am also looking into a better lighting system for my 58 gallon reef. I plan on going the VHO route and read about the Duro-Test Vitalites. I contacted them and they said they do not sell in the USA. They told me to try Maintenance Engineering. Do you have a source for these lamps? <No, but others are on the links pages on... the WWM site... Bob Fenner> Thanks, Bruce

algae (of some sort) I have a lawnmower blenny and some hair algae growing off my water flow director and he won't eat it. Could it be he doesn't know it's there?  <Highly unlikely... and almost as unlikely that this is a green algae that is palatable... Probably a blue green, aka Cyanobacteria> Should I just clean it off myself? How would I clean it? <Yes, remove the unit, lightly bleach it for an hour in a container, rinse thoroughly in freshwater, replace. Bob Fenner> Thank You, sandl

Tank Update and Nudibranch Question (refugium and algae control faqs) Hey Bob, Just wanted to give you an update on my tank. My nitrates are down to 30 after 3 weeks of weekly 25% water changes. Im still battling some hair algae but everything seems to be doing well.  <Ah, good> Since I have some left over money I have decided to buy a CPR hang on refugium. I want to put some of my remaining tang heaven and get some more algae to help me export more nitrates. Have you ever used one of these units or have you herd anything about them?  <Yes, we have some of Suk, Tom and the boys from Arcata (CPR) refugium units on test tanks... with about the same CF lighting we all use... We've been building, using very similar gear (ours have skimmers, calcium feeders on them in addn.) for years... these do work> Also, I have been seeing algae eating nudibranchs advertised on several web sites. (some call them sea hares) The also say that they are easy to keep. Is this just a marketing ploy or do these really eat hair algae and easy to keep?  <IMO/E more of the latter... don't like the use of Aplysiids (SeaHares) for this application... can/do cause some real troubles with water pollution at times... Would look to other algae eaters> I certainly wouldn't want to buy one to have it starve and die in my tank possibly killing all of its inhabitants. Thank You, Jonathan Pac <Good point... Do read, re-read the most recent updates on "Marine Algae", "Algal Filtration", "Algae Control" on our site: www.WetWebMedia.com here. Bob Fenner>

Crabs In your previous writing's on your site you have stated that the Mithrax crab's are good bubble algae and bryopsis eaters. I very much would like to have a few in my 120 Berlin system. Will they be ok with my red leg, and blueleg crab's and all of my coral's? How many would you recommend for my tank? As always , I am grateful for your site, books and advise. Thank you , and take care. <I would try four or so small individuals of the Emerald Crab <Mithrax> here... but no guarantees... there are numerous cases of this species trying out other crabs, even corals from time to time... Get one inch or so individuals... chances are they will leave your other life alone. Bob Fenner>

Algae Blennies Hello, I currently have a 20 gal. tank with about 19 lbs. of live rock, a coral banded shrimp, tomato or cinnamon (not sure which one) clownfish, a Banggai cardinal, 2 hermit crabs and some snails. My tank is about 2 years old. I had some trouble until I put in all the live rock. Lately I have been trying to keep an algae blenny but have failed twice. Could they have starved to death?  <Likely yes... take a look at the "Blennies" and FAQs section on our site: a Salarias will definitely not be sustained in a twenty gallon system... but there are some other (pictured) species that might (don't get as big, aren't as active), like members of the genus Atrosalarias...> I fed green marine algae in the dried sheet form. I also fed brine shrimp and formula 1 for the other folks. I am not planning on putting another one in but would like to figure out what happened. Thanks much! <Well done my friend. Bob Fenner>

interesting algae eater Hi Bob, I'm looking for an interesting creature to help get rid of the algae in my 50gal tank. Currently I have a Snowflake eel, a porcupine puffer, a long nose hawk fish, and a flame angel. (He relies a lot on the algae so I don't want something that's going to eat a TON algae). What I was thinking of is a Pink Pincushon urchin. But I don't know how compatible that would be with my other creatures. Also, I don't know how poisonous they are (I don't want anything than might paralyze/kill me) I did read your article on urchins at wetwebmedia.com. So what do you think, if this species is no good can you recommend a better urchin? If Urchin's in general are a bad idea do you have another suggestion for an interesting algae eater. (I know about the lawnmower blennies, I'm keeping that in mind as a backup if I can't find any better ones). Thanks for your advice. Steve Weatherly < Hmm... this is a bit of a tough question... as your tank is getting crowded... and will be with growth of your present fishes... I wouldn't introduce an urchin in your system though... too much of a temptation for your Puffer... it would eat it. And a Lawnmower Blenny is likely to be too fastidious... as I agree with your statement/observation... the Flame Angel greatly benefits from the live rock algae... If you are planning (you should be) on getting a larger system, I'd look into a Sailfin or Bristle-Mouth Tang species (the genera Zebrasoma, Ctenochaetus)... One of these will do a great "algae picking" job (start with a small... 3" or so diameter individual)... Review of the various species possible at: Home Page  Be chatting, Bob Fenner>

algae (and spelling) problem I have a 55 gallon tank with VHO lighting. I have been having a problem controlling the algae. In all of my other aquariums I have used tangs, snails, and hermit crabs to control the algae. I have tried using tangs, snails, and hermit crabs, but this tank contains a 5 inch Picasso trigger, a 3 inch Niger trigger, and an 3 inch undulate trigger. The triggers always kill the tangs, and eat the hermit crabs and snails. The triggers don't eat any of the algae. This tank contains a lot of corals so I cant put anything in that harms them. I have had the triggers for over 3 years know and I am getting close to getting rid of them. I have tied adding chemicals that claim to destroy alga and frequently sweep districts from live rocks. Any suggestions to control the algae and would that me keep the triggers and corals would be helpful. < Hmmm, triggers eating the algae eaters... Well, I would go the competing and chemical filtrant and stepped-up maintenance routes instead of predators (like snails, hermits, tangs). Competition for nutrients can be arranged through the growth of macro-algae in your main tank, or better in a sump with its own live rock and lighting would really help to make the "food" unavailable to the nuisance algae. Chemical filtrants will do the same. I would either use PolyFilter or activated carbon and replace it every month. Stepped-up maintenance includes cleaning your skimmer thoroughly, increasing the incidence and volume of water changes and gravel vacuuming (that will reduce the amount of available nutrients). Do these three and I'll give you my seal of approval (arff arff), that you'll have much less algae problem. Bob Fenner>

Snails & Crabs Bob, Do you have any preferences in including snails and crabs in a "live rock/protein skimmer" fish tank to help control algae? In another life I had freshwater tanks with snails - they do proliferate so fast it scares me! If I keep some hermit crabs will I have to also provide empty shells for them? I think I should. Many Thanks, Bob Andris < Actually I'm personally not a big fan of either snails or hermit crabs as algae cleaner uppers... There are many situations in which they can/do help, but also a bunch of situations... very common, where the types of "other life" kept (corals, sponges...) are bothered to harmed by their presence... I'm a much bigger fan of the various shrimps and fishes that can aid in such maintenance along with good set-up, operation and up-keep. Bob Fenner, who does "like" such animals in particular set-ups... trocihids in fin-fish culture for example...>

Biological algae control? I have a 125gal reef.... 200lbs of live rock.. (2) 175watt 10,000k MHs, (2) 160 watt VHOs. my skimmer comes off an empty sump and is 6feet tall with a 1000gal per/ hr pump on it.. I have about 100 crabs and 100 snails.. 4 serpent stars. 5 shrimp. 1 sand star. 2 clowns and I royal gramma.. >> < Any of those fluorescents actinic types? I would switch at least one, or add two others as actinics, have them come on one hour before and off one hour after the other lamps. For purposeful algae eaters I would definitely go the fish route: one or two Lawn Mower Blennies, a Sailfin tang or two (like a Yellow or Purple tang), AND a Bristle-Mouth Tang species of two (like a Kole, or Chevron)... Sound okay? It is! Bob Fenner, who knows you'll soon be wondering, "what happened to those algae problem days?">

reef fish that eat algae bob- I have recently asked a few questions in regards to my 58 gallon reef tank and your responses have been very helpful and reassuring that I am doing the "right thing". also, you have been very quick to respond for which I am very appreciative. this forum is a pleasure to read. my question for you today is about stocking my tank. I certainly do not want to overstock and I would like to have my fish peaceful with one another. currently I have 1 Percula clown and 1 yellow tailed damsel. I would like to add 4 - 5 more fish (if my tank can support them) that are well suited for a reef tank. in particular I would like to add fish that will eat hair algae ( I have a slight outbreak and I do know that there is not a "true" hair algae eater). I have been told that lawnmower blennies and purple tangs (also good with bubble algae) could be of benefit. do you agree and/or are there other fish that you believe would be a better choice. I am also interested in your thoughts on additional fish that aren't necessarily algae eaters but are reef safe. as always thank you very much, rob < Thanks for continuing input Robert. The Lawnmower Blennies are a very good choice, and there are many other blennioid species to come that are great algal munchers (including filamentous forms). The Purple Tang I have mixed feelings about. It's a great algae scraper, but gets quite large (more than a hand size) and therefore will take up a bit of space in your 58 gallon. Instead, I encourage you to check out some other surgeons that don't get quite as big as fast (and also are a little less aggressive). One unsung, underutilized hero is the Lavender Surgeon, Acanthurus nigrofuscus, sometimes available from Hawaii... The genus Ctenochaetus are excellent. These "Combtooth" tangs are avid filamentous algae eaters. Most often seen are the Chevron (C. hawaiiensis) which is a little pricey, but the Kole or Yellow Eye (C. strigosus) and Striated (C. striatus) are functionally just as good. And let's finish up with other Zebrasoma. The Yellow Tang (Z. flavescens) and Scopas (Z. scopas) are congeners of the Purple that are just as good as the Red Sea beauty, and much less expensive. There are many other algae eating fishes (and non fishes), including the ultimate for the price conscious, some of the damselfishes... Bob Fenner>

Establishing Nutrient Cycling, Controlling Algae First - thanks for publishing the Conscientious Marine Aquarist - it is a "bible." Re: I'm setting up a 15 gallon quarantine tank as recommended in your book for my existing established 120 gallon main tank. Does this tank have to "cycle" like the main tank or is the idea to change the water daily or every of couple of days so as to avoid the need to cycle? Also, should I attempt to match the substrate in the quarantine tank to the pink Somosa sand in my main tank? < Hello and thank you for your kind words. And good questions. Actually, I've found the best way to manage water quality in quarantine set-ups is to utilize the system water from the main/display unit. So, I guess it has to be cycled to be of much use. Alternatively of course, you can/could use some media from a friends system that is established... And the matching substrate? Unless the type of livestock being kept requires such, I'd leave it out... too much interaction with possible treatment chemicals... and a few other potential downsides. If there are organisms in need of sand, maybe put this in a plastic or glass container... to ease its removal... and moving of the buried livestock.  Any of those fluorescents actinic types? I would switch at least one, or add two others as actinics, have them come on one hour before and off one hour after the other lamps. For purposeful algae eaters I would definitely go the fish route: one or two Lawn Mower Blennies, a Sailfin tang or two (like a Yellow or Purple tang), AND a Bristle-Mouth Tang species of two (like a Kole, or Chevron)... Sound okay? It is! Bob Fenner, who knows you'll soon be wondering, "what happened to those algae problem days?" > thanks for the advise.. and yes the 1 VHO is actinic the other is 10,000k  < Ah, good. Thought so, but just had to check (and give a heads up to other folks who will browse this FAQ). Be chatting,  Bob Fenner>

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Marine Aquarium Algae Control

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