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FAQs on Algae as Food: Culture

Related Articles: Algae as Food, Foods/Feeding/NutritionCulturing Food Organisms, Culturing Macro-Algae; Red Algae in General, Marine Algae, Algae Can Be Your Friend

Related FAQs: Algae Foods 1, Algae Foods 2, Algae Foods 3, & FAQs on Algae Food: Rationale/Use, Sources, Feeding Methods, Troubleshooting/Fixes, Products, & Foods/Feeding/Nutrition 1, Phytoplankton, Marine Algae, Coral FeedingBrine ShrimpVitaminsNutritional DiseaseFrozen Foods, Coral Feeding, Growing Reef CoralsCulturing Food OrganismsRed AlgaeSee also the individual groups of organisms feeding FAQs files

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Marine Aquarium Algae Control

by Robert (Bob) Fenner

Chaetomorpha experiment     5/18/19
<Hello Naomi>
I'm really hoping you are able to help me, and I would greatly appreciate your time in having a look at my question.
I have been doing some experiments where I have been looking at the growth of Chaetomorpha to find out the best environment for it to grow, for a bit of fun and to sell what excess Chaeto I might get.
<Sounds good>
I set up a 100 litre plastic container, Kessil h80, added a 2000lph powerhead in there, put a large (20cm) airstone in there just to make sure there was plenty of flow which I know they appreciate.
I then set up a feed of Gaillard's f/2 formula.
The growth was great, it started weighing at 30 grams, and grew incrementally to about 180, with me having about 10% growth daily.
However, when it hit 180 it just stopped growing.
<Ahh; something.. perhaps things became rate limiting. "Law of the minimum". Or OTOH, there might be a situation where some factor is too much in abundance that is forestalling growth. Could be a nutrient, aspect of water quality, allelopathy... many possibilities.>
I did checks on all the parameters, as I was wondering if it was lacking something that was stopping the growth, but no luck all the parameters were fine (and I checked a lot). They were actually really quite high because the Chaeto had not been growing but had still been getting fed daily with Guillard's f/2,
So then I wondered whether it was because there was an excess of nutrients (though I didn't think this would be the case).
<Could be>
So I did a 100% water change, and continued feeding as I had done at the start, no luck, it stayed at the exact same weight, no dying but no growing.
<Mmm; good try, thought>
Then I did another 100% water change and started feeding it TNC complete in case the Guillard's just wasn't the right mix of nutrients. still no luck, stayed at the exact same weight.
And then I cut it in half, took half of it out. and there we had it, started growing again at around 10% per day growth.
I'm stumped why this is happening, the only thing I can think of is that the water volume is too small to accommodate it getting past a certain size, though 180 grams is relatively not that big for a 100 litre container. And with the large airstone and large flow surely it should not by a carbon issue?
<It (the reason) might well be simply the crowding, concentration/biomass of the algae here. The practice of regularly removing, keeping this at some optimum concentration is a common element of Macrophytes culture. Algae, and other life, do produce sorts of "negative feedback loop" limiting their
further expansion in a given environment, space, conditions.>
Do you have any idea how I can make it to continue to grow past this volume with the container I have?
<I suspect you are "up against it" in terms of growth, amount of Chaeto you can grow under present conditions. I do know, have experienced folks growing this genus (in Kona, HI) in "tumble culture"... i.e. in large circular pools (set up above water), utilizing air bubbles exiting from a circular pipe set in and away from the side of the pool, to keep the algae in constant, slow tumbling, allowing all a chance at sunlight, access to nutrients, release of wastes; utilizing open addition of new water,
flushing out old>
thank you in advance
<Thank you for sharing. Bob Fenner>
Re: Chaetomorpha experiment      5/18/19

Thank you for your amazing insight. That was my guess so thank you for clarifying it's great to get another perspective. I might have a rethink of what I could do
<Again; thank you... Glad we could share. BobF>

Caulerpa in a DT with tangs?       12/21/16
I have always loved the look of Caribbean reefs and would like to include vegetation in my 220 gallon mixed LPS/soft coral display tank. I also love watching the antics of tangs and am planning on including a few in this build. I have read several posts noting that tangs have kept Caulerpa (C. mexicana and C. prolifera, specifically) growth in check. However, most articles don't mention biological/herbivore controls and simply say "Don't do it". Do you have any thoughts on this?
<Some species, individual Tangs will eat "some" Caulerpas; but not all of either>
Are there similarly hardy and palatable plants I should be considering instead?
<Ah yes; for looks there are MANY choices, for function, Gracilaria and Chaetomorpha species are faves. These are gone over quite a bit on WWM if you care to delve into the subject>
Thank you for your time?
<Welcome? Bob Fenner>
Re: Caulerpa in a DT with tangs?       12/21/16

Bob! Thank you for the quick response and my apologies for the errant question mark.
<Heee! Figured it was an error>
I have searched through the WWM faqs and articles (for which I am eternally grateful) and haven't noticed/understood the answers so I apologize if I missed the appropriate posts.
<No worries; let's see if we can get you the information you're looking for here>
I was looking into the gracilaria in the DT but I'm a bit concerned the tangs would over-graze it.
<Yes to this. Need to raise elsewhere... like an illuminated sump, refugium, and only add to the main/display tank what you want consumed>
Assuming moderately high LED lighting for corals in a 72 x 24 x 30 tank, how much established Gracilaria would be recommended to persist, assuming 3-5 tangs (Likely candidates are Hippo, Yellow, Sailfin, & Convict)...
<As stated, raise macrophytes that are palatable elsewhere. NOT in the main tank>
and am I correct in assuming live is usually preferred (by the fish) over freeze-dried?
<Generally yes; though algae consuming fishes will learn to, eat dried algae with gusto>
I've also looked at Chaeto but are there forms that wouldn't trap detritus or which grow more...leaf like?
<Not so much as "spaghetti" like>
What about rooted Sargassum or anchored Halymenia?
<These and other purposeful algaes can be grown, used for a range of ornament to food... The browns/Phaeophytes, like Sargassum are a bit harder (than reds, most greens) to culture... Need/use quite a bit of iodine (ide-ate actually)>
There seems to be too little applied information available...or I'm just not finding it.
<Useful data, intelligent anecdotal info. is about; but not easily found. There are some good books, specialty websites like Advanced Aquarist, Reefs.com, ReefBuilders... to ask at (bb's) and read archives. Do send along specific questions!>
Thank you, again, for all your input!
<Certainly welcome. Bob Fenner>

query for growing pure culture of Amphidinium carterae    3/5/12
I am a MSc student working on a project for growing PHAs. I wanted to test PHA genes in marine Dinoflagellate Amphidinium carterae and wanted to know the quickest, easier and reliable method for growing pure cultures of Amphidinium carterae.
Waiting for your reply.
Many thanks
Mona Joshi
<Mmm, well, I did have three semesters in phycology back at SDSU, including one/last in culture... but this is way back, and am sure that there have been improvements in the last few decades. Have you been to a large/college library, searched for standard works, scientific papers on Dino culture? Even this species, or genus?
I would re-address your question to a school w/ algology/phyco. course/s, or contact the folks at the Southwestern Fisheries Center (NOAA) here in San Diego... which is where I procured my help all those years back. Bob Fenner> 

Refugium: Ok to use algae harvested to feed fish. 7/13/2010
Hello Wet Web Crew,
<Hi Wendy>
I have a refugium in the sump of my 180 reef tank which is growing macro algae.
I had thought that the algae grown in the sump could be used to feed my fish, but recently read something which seemed to indicate it would not be suitable for feeding since grown on 'fish waste'.
<Yes, it is grown on fish waste. but that isn't a problem.>
Is it safe to use for feeding my fish?
I've also seen different opinions on lighting the refugium and wonder what is best, 24 hour lighting, or reverse of main tank?
<I prefer reverse of the aquarium. It helps keep the pH up during lights out.>
Thank you for your thoughts,
<My pleasure.>

Algae Growth?/Growing Algae 5/6/10
Hi Crew,
<Hello Charley>
I have maybe an odd question, but how do I increase algal growth in my tank?
<Not necessary to do so, the freeze dried seaweed will provide this. Do consider a refugium for culturing algae, it will also improve water quality. Do read here.
My Yellow Tang is always looking for food on my live rock, but never, ever eats any. She finds so little vegetable matter that I have to add in two seaweed clips a day just for her.
<And a practical way to supply this food source.>
With the supplemented brine shrimp
<Not a very nutritious food.>
and seaweed she looks "pretty" healthy, but what's life with given food all
day, right?
<Do read here. http://www.wetwebmedia.com/yellowtang.htm>
Foraging seems so essential to their life, and I plan on adding a dwarf angel (flame or potter's, love the coloration of potter's but love the spunk on flame) soon.
<The Potter's Angel is not easily kept, better off with the Flame.>
I have 3 turbo snails and 7 other snails (prolly Astraea) for my 55g (moving in a month, getting a 125), so I don't think that's enough snails to take all the algae.
<I would hold off adding more snails in the 125, the tank will be too new and food will be scarce.>
Should I periodically turn off my sump and my protein skimmer?
<No, and for what reason?>
Oh I have a coral in the tank so the lights are power compacts, and I DO see coralline algal growth, so the rocks should be live...
<Not necessarily, coralline algae will grow on glass and I've never heard the term "live glass".
Thanks for everything!
<You're welcome. James (Salty Dog)>
Charley Teng

Phytoplankton culture and culture density measurement   7/7/06 Hello, <Hi there> I would like to say thank you in advance for your time. I have a few questions with regards to culturing phytoplankton. The purpose is for a small look at invertebrate larvae nutrition requirements. My primary reference is Dr. Toonen's 1996 "Home Breeder's FAQ for Marine Invertebrates". I am not a "real scientist" I originally only wanted to set up a nano-reef, but I got sidetracked while reading. <Sounds good> In establishing my culture, I'm planning to use local natural seawater (I'm on the coast of NC) that I will pasteurize. I am also planning to use the commercial Micro-Algae Grow formula as my nutrient. The phytoplankton cultured will be fed to invertebrate larvae (species as yet undetermined) that are maturing in aerated flasks (also pasteurized NSW, but no other nutrients added). Larvae growth will be measured by optical microscopy. 1. In order to determine if the larvae are feeding, I need to know the density of algae in culture at different points in time following feeding. I can do this by making cell counts, however: A Sedgewick-Rafter counting cell seems too large (1mL volume) for the densities recommended, even a Palmer counting cell (.1mL volume) seems excessive. There are gridded Sedgewick-Rafter cells available, including one from Aquatic Eco-Systems that is reasonably priced. Can I responsibly use a gridded cell? <Yes, I have used these> Or, because I cannot ensure an even distribution of plankton across the grid is this a bad idea? <Will be able to get enough distribution that by randomly counting a number of cells, you should be able to get good approximations> 2. Even allowing for a gridded cell, a microscopic cell count will take time. I know from your site and others, that it is not possible to get an accurate density measurement solely by eying the coloration of the culture, but I got the impression that this had to do with "eyeballing" the culture. I have the opportunity to pick up a used spectrophotometer cheap... If I measure take the absorption at x nm* for different densities of algae, wouldn't I get a reasonably accurate count of algae density? <Yes... a simpler device, a colorimeter (one set wavelength of light for absorption/transmission) will/would even work here. You can/should develop your own "curve" for density (counted) versus readings with this tool> *-where x would be determined by trial and error 3. This is the worst question I guess, and if you tell me to keep searching I understand: I find it's easy to get life cycle information (when it exists) for a species when you already know it's name, etc. But I have not found a database of larval stage characteristics of ornamental invertebrates. Could you recommend a test subject? Ideally it would be: a. cheap and common, b. externally fertilizing, c. easy to induce gamete release, d. has a planktotrophic larvae phase that lasts less than 2 weeks. <There is much known re "close" invertebrate species, but this takes a bit of familiarity, practice in "searching the literature"... I strongly encourage your visiting a large college library (of a school with a Bio./Zoology dept.), and having a Reference Librarian "show you the ropes"... Computer search bibliographies are very productive here... and a lot of fun... "Time whips by"...> Part d. is the hard one to search for. <Not too difficult as you will find> Again, thank you for your time. Your site is an incredible resource. -Tony <Glad to share. Bob Fenner>

Phytoplankton, reactor   7/4/06 Hi folks. I have been wondering if a AquaMedic Phytoplankton reactor would be useful in my reef tank. I have a 180 gal. reef tank with a DSB ( 275gal. total system water). Two refugiums are also running on this system. <Very nice> The first is a live rock with a DSB with blue light. The second is an upstream fuge with Chaeto and no sand with light running opposite. The tank has been running for seven months and I have gone thru the predictable algae bloom sequences. But the most fascinating event is when the macro algae vanished for no apparent reason. During the fifth and the sixth month I was battling Derbesia turf in numerous location on my live rocks. Early in the set-up I put two Emeral <Bam! Emerald> crabs in hopes to control this Algae. In addition I put a Sailfin Tang and a bunch of Hermits crabs and a variety of Algae eating snails to control it. Since the snails eat only Micro-Algae and the Emeralds might eat the turf Algae I wasn't convinced that they were guilty of eliminating all of turf Algae. My own theory is that I think the loss of algae was from the maturing of the whole system and the uptake of nutrients from the two refugiums. <Very likely the principal factor> All parameters of the tank are in normal range. Phosphate were high in the first three months and then zero. Currently my fish and coral list is Purple tang, Sailfin tang, Lemon Peel Angel, Lawnmower Blenny, Mandarin Goby, Sandsifting Goby. Coral: Ricordea, Euphyllia ancora, Frogspawn, Mushroom, Feather Duster, Crocea Clam, pulsing Xenia. My questions is does the lighted refugiums/scraping of algae off the grass provides enough Phytoplanton to feed the tank on a constant basis? <Mmm, plankton... is floating not attached... but likely the reproductive events of the glass-attached algae are contributing some algal plankton> I like the Idea of the reactor feeding some of my inverts plus provide foods for the zooplankton in my refugiums. <Me too> But Is it already happening anyway? <To some extent, yes> My other question is how do Copepods travel from the refugiums to feed my fish and Corals? <Yes... get "sucked up", pumped, or overflowed (depending on make-up of your systems components...)> Does it take some human intervention like stirring of sand or shaking of the refugiums? <Mmm, nope> Thanks for taking the time to answer every e-mails that come your way including mine. Sincerely Stephan <Thank you for writing, sharing. Bob Fenner>

Growing algae  6/25/06 - I seemed to have read somewhere I could place my own rocks in the sun to grow algae so that I would have a constant source of natural food for my yellow tang.  I am obviously doing something wrong, as I have had several pieces of dead rock outside in a glass, and even tried plastic, container for over two weeks and nothing.  Most days are very sunny with 90° temperatures here.  Any advice would be appreciated. Laura <<Laura:  If I understand correctly what you are saying, you are trying to grow algae on rocks outside in the air so then you can harvest the algae off the rocks or put the rocks back in the water.  Correct?  Well, I don't know where you read that; but, any algae that would grow on the rock outside of the tank would probably pollute the tank or not be the type of algae that the Tang would want to eat.  The better way to get algae to feed your Tang would be to buy Seaweed Sheets (called Nori) that the Japanese use to make sushi.  You can find Nori in most Asian markets.  In most pet shops they sell clips with suction cups that you can attach to the inside of the tank and clip the Nori to.  If you can't find the clip, you can attach some Nori to a rock with a rubber band and place it inside the tank for the Tang to feed on.  Best of luck,  Roy>>

Re: growing algae  6/25/06 - Thank you for your response.  I actually have the clip and Nori strips, but I was trying to give them a variety of food.  I am most appreciative of your help.   Laura <<Laura:  Glad to hear you already know about Nori.  I used to feed it very regularly and then I noticed a lot of algae building up on the rocks in my tank.  I realized that the Tangs would just sit around and wait for me to feed them Nori every day.  Now, I only provide it as an occasional treat and every one of them seems fat and happy.  If you don't have enough algae growing naturally to sustain them, and you want variety, here are some other options.  You can buy Julian Sprung's Seaweed Selects.  While fairly expensive (compared to Nori), they will give you variety you can buy off the shelf.  Another option is for you to learn how to grow Gracilaria macroalgae (also known as Tang Heaven because they like it so much) in a separate tank. Tangs will also usually eat Chaetomorpha macroalgae, though I have read that some people think it is not as good as Gracilaria for their Tangs.  If you do some more research, you may find other varieties of macroalgae that Tangs will eat.  Best of luck, Roy>>

DIY DT's I want to make my own DT's. From what I have found, all it is saltwater in a jar that sits under light and kept warm for a week or two. The water will turn green and then you have DT's. Is this true? <Not exactly.> If so how can they sell it for $16.00? There has to be more to this. <Please take a look at the following articles: http://www.reefs.org/library/talklog/r_toonen_102500.html http://reefkeeping.com/issues/2002-07/ds/index.htm> Thanks so much for your time! <You are welcome. -Steven Pro>

BGA in algae cultures The aquaculture facility I work for is encountering problems with BGA in our batch culture system.  The water used is filtered down to .35micrometers and it is UV'ed.  BGA is predominantly in our T-Iso cultures and is becoming a problem for the larvae it is being fed too.   Could you advise on how to eliminate BGA all together?  Any advice would be appreciated. <The S.O.P. is to bleach/acid wash the contaminated cultures and start over with Cyanobacteria-free culture media and Isochrysis... You likely know this already... sorry to be the re-enforcer of not-so-good news. Bob Fenner> Cathy

-Yummy, yummy Ogo- I have a Naso tang and it loves to much on "Ogo" (Gracilaria?).  I know that people use it in sumps for nutrient export, but currently, I don't have a sump (using a skimmer and LR/LS and regular water changes).  What would be the best way to keep Ogo fresh? In a bucket with SW? Should I run a filter? <It should be lit, kept at 76-82 deg, and filtered. You should be able to keep it for weeks like this in a bucket or small aquarium. Your Naso will thank you! -Kevin> Or just a powerhead?  Thanks. Yun

Too LITTLE Algae??   >WWM Gunk Guru: >>Surely you can't mean ME. >After months of fighting hair algae and Cyano-slime, I seem to have suddenly reversed fortunes. I have a Lawnmower (Jeweled Rockskipper) Blenny that has feasted for months since the setup of my 100 gallon reef tank on all kinds of single cell annoyances, gaining a stomach that would make a Hell's Angel proud. To give him some buffet dining partners, I added some small Sally Lightfoot crabs and a Rock Boring Urchin (true name, it's not very exciting to watch) along with 100 small blue leg and red hermit crabs, and about two dozen snails of various flavors. I've also upped my skimmer to an Aqua-C Remora Pro, and setup a nice little ozonizer that spits out 100 mg of O3 per hour and keeps the RedOx at about 310 mV or so. I've finally added a juvi Regal tang (Doryiatus disneyus) that has a bottomless stomach for algae ... and, I now have to squint like Clint Eastwood to find any algae at all. The drawback it that I've noticed my Blenny is losing some weight, and the Sally Lightfooters seem to have less and less to munch on. The Rock Boring Urchin cruises over the entire landscape much more frequently in what I assume is a heightened search for yummy green snacks.  So (here's the question, thanks for waiting) >>Believe it or not, my pleasure! >...have I over-controlled my algae? >>It certainly sounds like it, especially if you're relying on the algae alone to meet the dietary needs of these denizens.  Could it be time to consider setting up a 'fuge for macros? >I could stand to give away or lose everything that needs it, except for the Blenny, who was my first fish and has survived major ammonia spikes and a 10-minute fresh air dip... >><GIGGLE!> >Thanks, SLC >>Would it be out of the question to set up a 'fuge or otherwise supplement their diets?  If not, consider either or both options, with the additions of Nori and romaine lettuce.  Otherwise, you may very well indeed have to remove some of these animals, and I would start with the Sally Lightfoot crabs and some snails.  Crabs first, for sure.  I'd like you to keep the urchin, just because it's really boring.  Marina

Growing Gracilaria [*Note to Bob: Chris has shared with us a nice summary of his experience growing the popular macroalgae Gracilaria here. Perhaps we can place it prominently I the archives or FAQs for easy access/referral by the crew and WWM readers? Thanks, Anthony] <Will do, Bob> Growing Gracilaria 11/11/03 Hi Anthony, Thanks for your advise in response my previous email regarding the growth of Gracilaria. <always welcome my friend> I am just reporting back to you some good results on growing Gracilaria - Red Macro Algae. <much appreciated... this will be very helpful to add to the consensus for all to see/read and learn from> In the first 4 weeks I have been very successful in acclimating the seaweed as I have seen some steady growth... new fronds and full color. I feel have established a very suitable environment for this macro algae to grow effectively. Here are the specifications... 1. A separate tank - One with high nutrient levels. A tank dedicated to feeding just the Algae... but high Nutrient Levels a must. I add a silverside or formula 1 once a week.. but being careful to not overfeed the tank; over feeding may allow growth of diatoms and other competing micro algaes. <good points here: monospecific culture, as algae and plants are competitive (chemically and otherwise) with each other just like reef invertebrates. And the finesse of nutrients... not too much or too little> 2. Trace Minerals - I dose about 7-8 drops of both Chelated Iron and Magnesium daily and perform a small monthly water change to replenish calcium levels and other trace elements. <the need varies by system... but you are finding your way here. Excellent> 3. Cold water - best growth for Gracilaria in between 60 F - 70' F. <this is not necessary, although fine if it worked for you. Much Gracilaria is grown commercially in the shallows (at surface level) in the tropical seas on lines and tumbling in baskets> 4. Strong Water Movement - I have a 800 GPH pump  in the sump and it's  return to the hex tank at  a 12 " vertical spray bar which pushes & tumbles  the Gracilaria around the tank in a circular motion (like a washing machine). At no time is any of the seaweed just sitting.... it's always tumbling. <yes... excellent and often overlooked by aquarists> 5. Strong Lighting - I have a 125 Watt Fluorescent Blue Actinic bulb hanging directly above the water column. Gracilaria grows in deeper waters and does better with Actinic Lighting. <again variable here... the commercial culture of Gracilaria ("Ogo" of food fame) is done so at the surface of the water. But the genus is adaptable and wide-ranging. I would suggest more/brighter daylight here to most aquarists> Please let me know of any individuals who are interested in purchasing 7-8 ounce portions of Gracilaria at a low price. They can contact me directly at XXXX@hotmail.com. <do be sure to establish it well in your local market through the LFS and aquarium societies so that you can retrieve some if/when your colony crashes> Thanks! Chris <thank you very much for sharing this Chris. Its always good to pay it forward. Anthony>

Phytoplankton dosing schedule and amount? 5/29/04 WetWebCrew, <cheers> Thank you once again for your dedication to this "hobby"! <a labor of love :) > We have a 75 gal saltwater reef tank with a sump (total circulating volume of about 70 - 75 gals.  We have been culturing Nanochloropsis from Florida Aqua Farms in 2 liter plastic soft drink bottles.   <excellent> After about a week of starting the initial culture, I have moved half of the culture to a second 2 liter bottle to continue the culture and have started dosing the aquarium with the other half. <yes... critical to cut and freshen the culture for continued success/availability> My goals for dosing phytoplankton are to increase the biodiversity of the tank, feeding the pods, feather duster worms (all of which have grown out my LR), sponges (which have grown out of my LR and asexually reproduced), and my T. Crocea clam.   <all good... although your tank if its like most needs far more zooplankton. The culture of rotifers and refugium micro-zooplankton is as good or better (more useful) than phyto culture> Currently I am dosing one half of a cup of the culture each evening just before the lights go off - just pour the half of a cup into the tank.  We unplug the skimmer and leave it off for 2 hours when we are dosing the phyto.   <do consider a relay switch to turn this back on automatically... Radio Shack gadgets> The dose rate and amount are just something that I decided to start with since I could not seem to find a scientific consensus from my research.  Since I am culturing the phyto, I do not know the density of my culture.   <even still... near impossible to determine the demand in your tank.> Do you have any suggestions / guidelines on the amount of phyto to dose?   <really experimental... like any nutrient imported, dose in small, gradually increasing portions until you find the threshold, as indicated by the beginning o a nuisance algae boom or some such excess-nutrient indicator. Skim hard after that and step back down to last "safe" dose and ride that for a while. Periodically push the envelope to see if/when increases are necessary (just like adding iodine)> I assume that if I dose too little then the effect that I am desiring will not happen.  What is the effect of dosing too much?  Problems with water quality? <yes... more or less, although slight if you increase feedings small and slow> Thank you in advance! John Bullard <best of luck, Anthony>

Phytoplankton dosing schedule and amount 5/31/04 Mr. Calfo, <just call me "Anthony" please my friend... much nicer than what my family calls me at times <G>> Thank you for your time and knowledge to answer our questions! <always welcome> You mention: <<<all good... although your tank if its like most needs far more zooplankton. The culture of rotifers and refugium micro-zooplankton is as good or better (more useful) than phyto culture>>> I have a small refugium in my sump with crushed coral (no macroalgae at this point).   <the macro is not needed unless you wish to employ a species (avoid mixing species) for "vegetable filtration" (nutrient export like a bog or bog filter on a garden pond)> I was hoping that the phyto dosing would help to increase the pod population within my tank.   <not likely here... at least not to any appreciable extent. The crushed coral is very unfriendly to copepods and small smaller micro-zooplankton. The best you can hope for are amphipods to grow in crushed coral. Amphipods, however, don't eat phyto... they eat detritus and lean carrion (leaning toward a meatier diet... they even prey on small live invertebrates, larvae, eggs, etc.). While amphipods are great food for fishes, they are too large for most corals to eat. A fine, deep sand bed is recommended for copepods here (with or without mud/sediments)> I have also been considering culturing rotifers.   <excellent idea> I wanted to get experience with culturing phyto before taking the leap in to rotifer culture (since rotifer seems a bit more complicated and one needs phyto anyway).   <do get a catalog from Florida Aqua farms... they have all manners of kits and supplies for rearing zoo- and phytoplankton> Too increase the zooplankton population what are your suggestions?   <it depends on what exactly (mysids, copepods, amphipods, worms, etc.) you are trying to grow. All do not fare well/equally in the same substrate. Its tough to sum up in the brevity of an e-mail too. May I suggest you check out our newest book "Reef Invertebrates"... it has the most extensive coverage to date on refugium methodologies. With live sand, live rock, plants and algae chapters, its over 100 of 400 pages> What does the rotifers do for the system besides adding zooplankton to the system (I am familiar with their uses with feeding larval fish)?  What is going to feed off the rotifers? <a majority of corals and other filter feeding reef invertebrates including some of the small(er) polyps species> Thank you! John Bullard <best regards, Anthony>

Kole Yellow Eye, feeding stones I read your article on wetwebmedia.com and I was particularly interested in the section on feeding. I have a yellow eye that caught ich but I was able to treat him in a quarantine tank for a few weeks. He has been back in my main 75 gallon reef tank for three weeks but seems to be on the skinny side and very pale. I was interested in the sentence that you stated "My favorite "gimmick" with these fishes is to utilize an algal covered "feeding stone" as a site for engendering food-taking behavior". What exactly is a feeding stone and where might I get one? If you have any other advice on getting him enough food would be greatly appreciated. Thanks! Cauley <"Feeding stones" are actually made by the aquarist... either in an aquarium (sans algae eaters) or in other containers (like large jars near a window), but you won't want to wait to make these. Do look into buying some palatable macro-algae... either from an online vendor like Inland Aquatics or Indo-Pacific Sea Farms, or perhaps a local retailer or hobby-club member. Bob Fenner>

Phytoplankton reactors 9/18/04 I was able to meet Bob Fenner recently in Raleigh and really enjoyed this.   <he is larger than life... blessed to know him> I also now have Anthony's propagation book and it is outstanding.  I was hoping to get feedback about a phytoplankton reactor. <all good... but do realize that in aquaria, the overwhelming demand is for zooplankton. Very little phyto is needed to support this. It is commonly abused as a supplemental staple IMO> My interest is in diversity and nutrition, especially nonphotosynthetic animals.  I'm trying to replicate cryptic environments.  The Dendro thing fascinates me (as it does everybody).   <do consider other/better aposymbiotic cnidarians like Scleronepth.s and Chile corals> My background is clinical neurology. The experimental system I have consists of a 120 connected to an Ecowheel with a wave 2K, a 120 with Turbelle stream 6200 on controller set up for laminar flow around a  central divider, two twenty five gallons for experiments with refugia, and a 75 sunlit and compact fluorescent tank DSB currently culturing Chaetomorpha.  I am underwhelmed by the Ecowheel.  The system has a 75 gallon sump with a large Reef Concepts skimmer;  automatic top off and water changes via LiterMeter, SG 1.026.  I have tried feeding Corals and Clams cryopaste and am still working with it.  I have plans to construct a small greenhouse to continue this type of research.   <fantastic to hear... do let me/us know if we can be of help with shared opinions> I do think that stirring the sand bed is the best thing going for nutrition.   <very helpful... agreed> The detritus is recycled not added, and interestingly I have noticed that the sand bed diversity is clearly greater in areas that are gently blown off twice daily compared to nonstirred areas.  I really think a little storm activity is good for the sand bed.  I drain off the turbidity slowly over the overflow into the sump, and then to the tanks. <the reef is quite dynamic even in the calmest parts... much more than our tanks> My question is about a phytoreactor that I have going in one of the 25s. I have grown green water for years- sometimes unintentionally!- and this is my first attempt at a phyto reactor.  I used DT's to start;  I currently add no nutrients.  I am not stirring- this setup reminds me of the saltwater tubs Joyce Wilkerson described that she keeps outside for rotifer cultures, and that emboldened me to try not stirring, no airstone.  The pH gets high and slows down the growth.  I think the pH is more steady when the lights are turned off at night allowing some digestion and co2 release.  Perhaps the lack of stirring will help phyto diversity. I am concerned about toxins generated from this reactor.   <weak issue... no worries> I'm not sure of the benefit compared to Reed Mariculture cryopaste.   <live is better than any processed product IMO on one glaring point - particle size. Most always smaller with live (no clotting or coagulating in time)> The green water probably contains lots of things- ciliates, bacteria- and it does seem (Bob Stark) that there is already plenty of bacteria in our tanks. The reactor does seem to pull out nutrients well- discarding the stuff seems to be an effective microalgae scrubber.  I think we know a lot about many of the filter feeders- and the ones of most interest to me, the "Dendros", seem to only take SOME of their nutrition from phyto.   <true... some take none at all... bacteria, floc, other nanoplankton>      So, the questions- 1)  Do you know anyone who has long term success with a phyto reactor like mine?  Any suggested improvements based on this experience (stirring/air, UV, getting rid of it and using cryopaste)? <phyto culture is a science... many people have refined techniques to learn from. Have you chatted with the folks at Florida Aqua farms? Pioneers and suppliers> 2)  Any news about successful experience with Dendros from somebody knowledgeable? <none I am aware of recently... rather that not all aposymbiotic Nephtheids in the trade are Dendros... which is a good thing. Seek Scleros instead when you can find them> 3)  I am going to visit GARF, inland seafarm, and Tropicorium in February for my 50th birthday.  Do you know of any really professional greenhouse outfits I might also need to visit? <I like Tropicorium and Inland Aquatics very much. medium sized scale but quality personnel. Most of the outfits farming reef inverts in the US are cottage industry sized. But you may want to see about a visit to ORA in Florida some time... after they recover from hurricane damage> Thanks so much for your advice Charles Matthews MD <best of luck, Anthony>

Tang food/algae? 2/11/05 I have recently purchased a Sailfin tang as soon as he was in his new home he proceed to eat a green plant that had came on the live rock which I think is Caulerpa. Could I grow this in a small tank 12 by 10 by 10, using the old water from weekly water changes and lighting with a full range Fluorescent light, <it could... but there are much easier and less noxious algae to grow. Gracilaria would be ideal tang food... sold as "tang heaven" from IPSF.com> would I need a heater or a filter maybe a little live rock? <yes... bright light too. At least 5 watts per gallon> I would like to do this as the Sailfin seemed to like it but there's not that much of it and I thought it would be a nice supplement to its diet, <a nice idea, but not necessary. Do look for "Nori" seaweed at an Asian grocery store or sushi supplier> assuming it's ok for it to eat it. If it's not is there any thing else I could grow with a similar method that would be ok? <it is somewhat to very toxic over time (Caulerpa) in large portions. Do avoid IMO> Thanks, Andy <best regards, Anthony>

Pyrocystis fusiformis - 12/11/05 Greetings from snowy Pittsburgh! <<Hello from a bit more temperate SC!>> I just wanted to thank you all for your efforts. <<Very welcome>> I'm new to the aquarist lifestyle and I'm happy to report that my 90gal FOWLR has been quite successful in the past 4 mos. largely due to the wealth of information you guys <<and gals>> provide (the site frequently keeps me up till the wee hours of the am). <<Hee!>> I have one quick question (for now): I came upon an interesting suggestion in the Phyto FAQs, where a man suggested growing Pyrocystis fusiformis in a FOWLR tank.  I was wondering if there has been any update on his activities or if you have encountered any new information regarding its toxicity to fish, LR or even SPS/LPS corals (before I try my own culture/controlled experiment). <<If you didn't find any on the site, then likely no new info/updates.>> The web info I usually find references the plankton as a "neato" school experiment. <<Let me suggest you try contacting some of the commercial fish/seahorse breeders ('Ocean Rider' comes to mind).  These folks culture their own phytoplankton from necessity, and if willing to share info, may be able to help.>> Many thanks, I'll be writing again soon. Regards Brandon <<Regards, EricR>>

Gracilaria parvispora culture  - 02/16/2006 Hi, <Hello> I would like to start growing Ogo as a food source for a few yellow tangs.  My problem is it is expensive and a screw up would be costly.   So I would like to run my plan by you before I start.  I will put the Ogo in a 10 gallon tank, lighting will be 96 watts from power compact bulbs, and water motion will be provided by power heads pumping a total of 560 gallons per hour (more if needed). <Not needed... circulation can be much less vigorous> Nutrients will be provided from water from the main tank, and possibly from frozen food juice added once a week.  I write this because after reading from your archives I am kind of discouraged from others not so successful attempts.  Any tips or suggestions would be appreciated. Thank you, Aron <? Not difficult to culture... I would boost (through new water additions) the alkalinity and biomineral content... 12 dKH, 450 or so Calcium, about three times whatever calcium is in Magnesium concentration... and keep out other algal species... Bob Fenner>

Ogo and quarantine   03/07/06 Hi, <Aloha> I ordered some Ogo from Indigo <Hee! Will send to Gerald, Heslinga... Indo-> Pacific Sea Farms about a week ago. It is currently in a 15 gallon qt tank. It is under 96 watts of PC light, and it is being tumbled around by a powerhead which might be too powerful.  Salinity is 1.025, temp is 80 degrees, PH 8.3, no ammonia nitrite or nitrate, calcium 400, and the water is RO/DI. My problem is I don't know if it is doing all that well. The plants <Algae> are still red, but the tips might be turning slightly white. <Not atypical> Is this from two much light? <Likely "just" shipping, stress> I would hate to lose the Ogo before I had a chance to use it, so is it safe to add some to the tank for food for my tangs, <Yes> or should I wait the two week quarantine period. <Are you concerned re Aiptasia, or? I would search through it, feed a bit off, move some to other quarters for culture (if you have them)...> I contacted IPSF and they said quarantine was not necessary, but I am still a little leery about putting it in the tank. So do you think this okay, or should I wait? Thank you, Aron <I wouldn't likely wait. Bob Fenner, who will eating Gracilaria in po'kes on the Big Island in another day or so>  

Harvesting Chaetomorpha   03/07/06 Hello Crew, Once again I would like to thank you for the fantastic site. Your hard work is greatly appreciated and I advertise you to all at the LFS and friends in the hobby. Most think with good reason I am a WetWebMedia junkie. <I look forward to your joining us in responding> It has been suggested that  several of us at work join A.A. ( Aquarist Anonymous). I am always referring them to do queries on your site when they ask a question of me. You previously helped me out with plumbing my upstream 30 gallon acrylic sump/refugium. The refugium has been up and running for about one month and all is going well. I had a very mild case of BGA after the first week it was running but increased the flow and vacuuming out the BGA reduced it to nothing quickly (thanks to reading your suggestions to others.) <Very good> Many copepods, amphipods, and worms thriving and are gravity fed to the main 55 gallon display tank.  My original double softball size Chaetomorpha macroalgae has grown into what is now basketball size or better. <Keep trimming, feeding, trading...> The ammonia, nitrite and nitrate levels are now undetectable with my Aquarium Pharmaceuticals Saltwater Master liquid test kit. Ph is holding steady as a rock at 8.4 with the reverse lighting cycle. <Simple, eh?> I continue to do 5 gallon water changes twice a week and Aqua C Remora attached to the refugium is still producing skimmate but I might add not as much since the refugium stabilized. Now for my question about harvesting the Chaeto. I looked thru the many pages of refugium and macroalgae area questions and answers but did not see a definitive description of pulling out the Chaeto properly. I know I need to do this on a regular basis. I am unsure what is and when is the proper time and procedure for doing this? Do I just grab a handful and pull it out? <Yep> I have attached a couple of pictures of the refugium and Chaeto. The dimensions on the refugium area of where the Chaeto is are 15" x 12" x 17" (height x width x length). Do I need to start harvesting now or wait until it has covered the entire refugium area? <I wouldn't wait... keep pulling...> Thanks you so much for your educating this want to be aquarist. Ernie from Kansas <Weekly is a good interval, while you're "fooling with" other maintenance. Cheers, Bob Fenner>

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