spirulina growing

I have assembled equipment and found resourses to start growing spirulina indoors.  I will use a 10 gal aquarium with a heater and air pump and LED blue red grow lights.  The idea is to eat 3 to 6 gram of spirulina a day and supplement our diet with vitamins minerals and enzyems not found in todays food.  We cant seem to grow enough of our food to insure those nutrient levels.  We have found commercial spirulina to boost our energy and mental alertness as well as regularity.  It is better, cheaper, and simpler than taking lots of healthfood supplements.
F/2 Guillards formula is the initial nutrient I shall use.  It is the standard algae feed used since the 70's.  I will compare the results with commercially grown spirulina and consider additional addatives.  Later on I plan to buld an outdoor pond and grow algae from a biogas digester affluent as animal feed supplement.  Both require temps in the 90's so will burn the gas to maintain that as well as using solar gain and greenhouseing.  Our hot summer days will often fall to 70 deg. at night here at 3500 ft. elevation.
Any thoughts or suggestions?  Anyone doing this?  Care to share your experience?

I've been interested in this, but as an animal food supplement, for rabbits, chickens, and pigs.

Do you know of any online resources that don't require workshops or large fees?

The biogas digester integration is interesting.  You could use a hot compost pile to help keep the temps up, similar to Jean Pain's water heating system.

I don't see many people actually doing this at home, but it is a very interesting concept.

LED lighting for that much algae may not be sufficient, in fact I am 90% sure it is not.  What kind of filter system if any are you using?  Go to an aquarium store and get a reputable submersible heater and that will help your water temp problem.  I used to build custom aquariums and filter systems for salt (cold & warm), fresh & brackish water, as well as vivariums so I am really interested in getting that part of my brain helping you out if you need anymore. 

velacreations asks for online info......
www.wardsci.com for culture of spirulina.  It is only  50ml and the next day shipping costs more than the $6.00+ culture so order a couple.  Have your lab set up with nutrient and ready to go to reproduce in larger quantity that you can use to start your factory.  See Ward's info pages for data.
www.AquaticEco.com under "live feed" find algae grow mass packs for Guillards fomula in dry convienent form.  This is the standard algae nutrient but will require bicarbonate to raise PH.  This will do for the edible algae.  For larger scale feed production may be to costly,  hence the use of digestor affluent.
For general info www.austrailianspirulina.com.au and several others that you can google.
As for the compost keeping the biogas digester warm that would only work well if you used a bag type digester and could heep the compost over it.  I plan on a floating drum over an above ground tank, solar hot water heated.  One reason to do this is because I have to much byproduct from making biodiesel to dispose of than composting can handle easily.  An anerobic digestor will produce gas with it as well as gas from humanure and emultified WVO or rancid WVO.
Pakanohida wrote that the LED may not be enough light.  Each lamp consists of 225 little L.E.D. bulbs alternately red and blue.  The aquarium will be in a south facing window for sun on one side and the top with a lamp at each end and the room side.  Each lamp is only 5 watts and operating 16 hours a day is less costly than a 40 watt flourecent.  I have a 50 watt aquarium heater that seems to do it for up to 90 deg/F.  No filters because I want the algae to grow and the nutrients to circulate not be filtered out.  A bubbler will move the algae into the light and prevent settling of the nutrient, also providing ample CO2 to the spirulina from the air.

a compost heater could work just the same as a solar water heater.  Just run water lines through the pile instead of a solar panel. The nice thing about compost heaters are that they are 24/7.

How are you making biodiesel? Are you making from algae?

What is running all of the energy needed for this setup (heater, lights, bubblers, etc)?  It seems like a lot of energy for a food supplement.

velacreations wrote:
a compost heater could work just the same as a solar water heater.  Just run water lines through the pile instead of a solar panel. The nice thing about compost heaters are that they are 24/7.

How are you making biodiesel? Are you making from algae?

What is running all of the energy needed for this setup (heater, lights, bubblers, etc)?  It seems like a lot of energy for a food supplement.

How can a compost or solar water heater be regulated successfully?  It seems like incredible overkill. 

I regulate my solar water heaters with a pump and differential controller.  Very simple.  When the tank gets hot, it stop pumping.

I make biodiesel from WVO(Waste Veggie Oil) which is free and abundant.  Easier to acquire than to make algae in fact I have 1200 gal. plus on hand.  I am on grid but offset all the power with 6kw solar and 1200 watts of wind power and I also run a biodiesel fueled generator to keep power bill to minimum.  Total power for the algae is only 70 watts for 50kwh a month, about $8.25, not enough to purchase two ounces of spirulina.  However the point is a sustainable superfood source, independent of health food industry, and later, fodder for the animals from waste. 
Utilizing salvaged solar hot water panels and themosyphon the above ground biodigestor will get more heat than available from my one active compost pile.....200 deg.F. without a pump compared to 140 deg. with pump.  With thermosyphoning the hot water must be hot enough to raise from the collector to the reservoir.  The reservoir is is a vented jacket on the steel biodigestor tank.  The volumn of water in the jacket would prevent over heating in sun and cooling at night.  Also a side arm biogas water heater will probably run on cooler nights.  As a fail safe the algae pond can act as a heat dump if an alarm sounds.  This is all speculation at this point.  I am still learning how to grow spirulina inbdoors for human consumption.

Elspru, that is quite a system.  I have several aquaphonics systems that I run but not in habited spaces.  I live a mile from a blacktopped road and 15 miles from an interstate, 50 miles from a town.  The nearest airport is about 100 miles.  Polution or contamination here is very slight and not  in my lifetime.  Every other square mile of land here is undeveloped desert grazing land operated by BLM.  Our big problem here is heat and dust.  Winters with the house closed, no problem.  Summers we cool with evaporative coolers, which in efect scrub the incomming air as it cools with water droplets.  The Problem was the outside air delivered by the fan would soon pressurize the house and stop flowing.  My solution has been rather than open a window to let out air  and  admit heat and dust to put a 12in. ten foot stack on the house venting rooms to it. The stack is painted black and thermalconvection draws air out but a wind driven turbine vent on the top assists.  The ceiling vents to the stack do not close tightly so some air passes even when closed in winter to reduce drafts.

wow 50kwh a month!  That's more than I use for my entire house!

The algae you could harvest from that doesn't even have enough energy content to cover that energy cost.  That is definitely not sustainable.  I think I will stick to permaculture (low energy) techniques for animal food production.

Interesting about the WVO, do you make it into biodiesel or use it as is?  I find it interesting that you claim it is free and abundant, but it costs both money and energy to grow the oil crops for that WVO.  Using it for vehicles is not necessarily the most sustainable option, as it can be recycled fairly easy (the majority of WVO is recycled in the US).

So, I assume you will be using the glycerine as the feed for your biodigester.  Have you run any tests or sample to see if it produces biogas?

After I posted last I realized that my numbers were way off.  I have a timer on the lamps that only run them 16 hrs a day, the heater is thermostatically controlled and probably runs only at night in winter.  It is more like 600 watts a day or 18 kwh, $2.95 a month.  I spend 10 times that in health supplements each month and up to $200 a month in feed.  I have niether the water nor the land to raise grains or grasses.  My goals with this are to grow at home, a super food and and have a high protien catastrophy proof food and feed. 
I run my beater 84 Isuzu pup for feed and oil pick up etc. on biodiesel.  I run an 83 pup with canopy and a/c  on biodiesel for shopping going dancing etc.  I get 30-36 mpg, and remember it is over 50 miles to shopping.  I run biodiesel in an oil heater to heat the house and greenhouse.  I run the generator on biodiesel and am working now to set up a heating system to run it on straight WVO at 160 deg.F.  I save about $5k a year in fuel for a modest investment in time and equipment.  The restraunts I pick  up at are to far out and use to little to get commercial recyclers to pickup.  They were puting it in the dumpster.    It may not meet your sustainability standards but it is great for me.
The byproduct of biodiesel reportedly increases anerobic digestor gas output proportionately.  See www.dickenson.edu.  It is biodegradable and I do run it into my compost heap, to much will stop the action.  I am experimenting with a still to recover the methanol  and am not totally satisfied yet.  The methanol would turn to methane in a digestor.  The other feedstock will come from humanure.
Valecreation, I scaned your web page.  You may consider keeping activated charcol on hand for times like when Leo got sick.  It stops upset tummies and the runs quickly.  It will work on over 3000 differerent poisons, virusis etc.  You can make your own with burnt toast.  Do you butcher
the hogs?  I have one ready now, not fun.  I have 6 baby rabbits out of my three does.  Another litter due this week.  We are having rabbit catcatorie tonight for dinner.

velacreations wrote:
I regulate my solar water heaters with a pump and differential controller.  Very simple.  When the tank gets hot, it stop pumping.

Yeah, like I said earlier, that's great for solar water heating for personal use, but not for maintaining and aquarium where you want it to flux as little as possible.  I am more of an advocate for submersible water heater unit for a aquarium tank still. 

They were puting it in the dumpster.

If they are putting it in the dumpster, then yes, what you doing is much better.

I don't doubt that the glycerine will digest, I just haven't seen a lot of info on that.  I imagine that you'll need to mix some carbon with it to help balance things, but it might work well. Adding humanure will be a great addition.  You can also add pigs and rabbit manure, as well, or use Black Soldier Flies to harvest the nutrients out of the manure, and then feed the BSF to your pigs, and their waste to the biodigester.

18kWh is still a lot.  how much algae (in pounds) are you harvesting a month?  You would have to harvest tons to make back that energy.

Yeah, I do want to start keeping activated charcoal on hand.  it is good for a lot of things. Leo so rarely gets sick that it isn't really an issue, but it would be good to have some on hand.

Yes, we butcher the hogs and also sell them as finished hogs to our neighbors.  If you have never done it, try and find someone who has, pay them for their time, and learn how to do it.  You can always hire it out, if needed (it is a lot of work).

Rabbit is excellent meat, and of all of our experiments, rabbits are by far the most productive.  We are to a point where we have them kindling every week, and we sell the surplus meat to neighbors, and my wife tans the hides.  We feed the offal to the pigs, the heads and feet to the dogs, so everything is completely recycled.  The manure goes to worms and the garden.  Countign the young ones, I think we have close to 45 right now, but it fluctuates every week, cause I usually kill 5-7 a week, and 5-7 are born every week!

i butcher my own hog but like I said "it aint fun". I do not have space to do more than one hog at a time and no pasture so need buy feed,  I do get some spoiled stuff from the local food bank.  What do you do with the offal from a large pig?  I have been burying it in the fenced in gardens with some increase in produce.  I do not try to sell animals or meat.  All the effort and expense is best kept home as superior product.  If my freezer is full I may sell a young goat.
I keep my rabbits in a small barn, in cages.  It gets over 100 deg.F often in summer and so I run an evaporative cooler for them on a t'stat that starts at 85 deg.  Like the coolers in the house it runs off solar.  Even so I do not breed them in July and August.  A doe just kindled yesterday, so that gives me 12 young and three does, one buck.
I am on grid and have 6 kw of solar and 1200 watts of wind power plus the generator to run if the meter is to high.  So 18 kwh a month is not a big deal for me.  I am just getting the algae set up and running and do not have product yet.  Judging From commercial spirulina, the most you want to take is a teaspoon a day(three grams).  More than that with a regular diet wires you up and interfers with sleep, even so dont take it late in the day.  So two adults in a month can only use less than a pound.  If no other food is available, we could live on a pound apiece per month and be healthy.  In which case the system could be ramped up to provide that.  Given ideal conditions spirulina will double in volumn in 4 or 5 days.  So in extremis we would not have to eat our breeing stock or go hungry.  By harvesting less often and adding less nutrient we will be able to hold it at 12 oz. a month, which is all we need.

spiritrancho, I'm looking forward to pictures of your setup!

All offal goes to other animals, like chickens and dogs.

We have lots of surplus, so that is why we sell.  It helps to offset expenses.  We only sell to neighbors and friends.

You might consider setting your rabbits up on a colony system.  We have hot summers as well, but in the colony, they are able to burrow in the dirt and stay cool.  We never have an issue with overheating.  The cages are definitely harder on the rabbits.

Yeah, 18kWh is a lot of energy to produce a pound of food, which doesn't even have an energy content of .5 kWh.  So, your conversion rate is 36:1, at best.  You should experiment with growing without so much electricity.  Solar heaters could help with the heat, and putting them outside in a greenhouse or protected setup would get rid of the lights.  Energy conversion is not about cost of electricity, it is about efficiency and sustainability.  If it takes 36 units to yield 1 unit, there is a big issue there.

I find it extremely hard to believe that you could consume a pound of food (with extremely low calorie content) a month and be healthy.  Have you ever tried it, or now of anyone that has done that?  Algae is low on calories, and although it is rich in minerals and vitamins, you could not live on it alone.  If you know of someone who has for an extended period of time (more than a few weeks), let us know.

I definitely like the idea of a good nutritional supplement, like the algae.  But we need to find ways of producing it without large inputs of energy. 

The protien content of spirulina is higher than any other food except eggs.  I read about a Japanese monk that lived on spirulina alone for 15 years.  He raised it in a pond using his own pee as nutrient to assist the minerals in the pond.  I can attest to the energy boost from just a gram of the stuff.  In fact I have learned not to take it after noon,  it messes with my sleep.
Using the lights in addition to the south facing window is to increase production.  Using a bubbler is to keep the spirulina in constant motion, rather than stirring it now and then...again to increase production.  Using the 50 watt heater keeps it at optimum temp for maximum production.  The heater has a T'stat and will cut off regularly.  Untill I get a good understanding of the operation and yield I will do this way.  If later on I see that the production is to high I can cut back on heat or whatever.  Perhaps I will end up going to just one lamp.  No one can tell me I have to learn it on my own.  My goals are to first provide vitamins and mineral rather than buying supplements.  Secondly to have another  sustainable source of food come hell or high water.  My third purpose is to learn enough to start up a low cost supplemental feed for animals using cheap renewable resources.  The later will be energy efficient.

I have read stories of that Japanese monk as well, but it's all been hearsay.

Still, spirulina is awesome.  I should grow some myself.

I'm waiting for a verified source that says you can eat a pound of low calorie food per month and be happy.

The protein content may be higher, but you are only eating a pound of the stuff, max.  And it doesn't have hardly any calories.

Again, it is great for vitamin/mineral supplement.  But you can't live on a multi-vitamin, you need real food as well.

And 18kWH per month for a multi-vitamin is NOT sustainable.

Vela'  I have lots of canned veggies, meats, dehydrated and frozen food in storage plus fresh food in the ground and on the hoof.  So in the event I cant buy good food we will still eat long past a catastrophic event.  Most stored food has been processed and aged enough to deplete the enzymes and reduce the vitamins as is true with all cooked foods.  The point is not energy effciency but staying healthy, daily and in the event of lengthy isolation.  You wont have proof untill you take spirulina and see the value of it.
One could argue that keeping chickens for eggs is not worth while when eggs are so cheap at the store.  The same is true for spirulina.  Home grown assures supply and freshness and quality.  If that does not meet your sustainabiity standard...dont do it. 

You wont have proof untill you take spirulina and see the value of it.

Actually, if someone provided evidence of living a month on algae, I would take that into account.  Unfortunately, I can't find such evidence.

One could argue that keeping chickens for eggs is not worth while when eggs are so cheap at the store.  The same is true for spirulina.  Home grown assures supply and freshness and quality.  If that does not meet your sustainabiity standard...dont do it.

You are confusing cost and quality for efficiency and sustainability. Home grown eggs are usually more energy efficient than store-bought eggs, thus justifying a higher price.  They also consume kitchen scraps and other "wastes", thus increasing the efficiency and sustainability of the entire system. 

The only way you can produce your algae at a 36:1 energy to product ratio is because of the cheap energy provided with fossil fuels.  Take away that cheap energy, and you will have to be a lot more efficient, which means your algae goes away.  So, you see, it is not sustainable.  Something that survives with only large energy inputs is usually not sustainable.

How would you explain that your system IS sustainable?

Or maybe the question should be "How can the system be tweaked to make it more sustainable?"

Or maybe the question should be "How can the system be tweaked to make it more sustainable?"

Yes, that is definitely more appropriate.

Burra Maluca wrote:
Or maybe the question should be "How can the system be tweaked to make it more sustainable?"

Interesting topic. Nutrition of spirulina is new to me. Setting up a system that requires only solar inputs and can maintain a constant temperature should be relatively easy. I would think you could do it with thermostats and heat storage tanks along with a solar panel and batteries for your LEDs (if you want them on all the time). Otherwise, a solar light tube or several for added light could do the trick.

could be I do not understand the whole setup, but thinking this might be something good to add into a whole permaculture design.

Elspru-  have only seen a sky like that here on one occasion.  We do have an airforce base 120 miles north.
Vela'-  My energy is cheap because I make it from waste veggie oil, solar and wind, not fossil fuels.  I only use the grid as a cheap storage bank.  You are preaching to the choir, Vela.  Cost, efficiency, and maintainability, and utility define sustainability to me.  It remains to be seen if spirulina can be maintained or not, then we can look at reducing the energy required.  The utility of the stuff has been proven by experts.  Research it and see for yourself.
Bara, I will report my progress.  The first steps are to see how long I can keep the culture going without having to order more.  If it dies off in several generations it wont be worth the trouble.  Also, can I harvest enough to be useful?

After less than a month I have harvested 5 grams of spirulina (dry wieght).  The little tank is not as dense as expected yet, but filaments of the algae were coating the sides and reducing the light to the media.  So I scraped some off and set it to dry.  So the system does work, even with the primative methods used.  After it gets dense enough to tell the differnce I will start some experiements.
The jars of media and culture in the aquarium totally failed.  Only the media in the aquarium gave algae.  It is getting denser every day.

After growing the media for a month the pics below show one days harvest of 8 grams dried and a shot of the spirulina with bubbler and LED.

I am totally new to this and am trying to find simple basic step by step instructions to start growing spirulina in an aquarium (or easily indoors for personal consumption). I know next to nothing. Is anyone willing to help point me in the right direction to get started? For example a list of what to buy to get started, how to set it up, where to buy the culture....Once I get started, then I'll know what questions to ask to fine tune the process. Most of the info I'm finding on the net assumes a scientific knowledge that I don't have.
Thanks for the help!

Curious, If you will read the posts above I document all the suppliers and the method I use.  One note, I recently decided I did not require the heater so shut it off.  I did fine untill I harvested and added 5 liters water and nutrients.  Then the temps droped and and I went a week with no yield untill I got the temp back up. 
For those times when I do not have a harvest or am to busy I keep powdered spirulina for use in smoothies and stuff capsules in case no time for the juice.  The cheapest I have found is the NOW brand at Lucky vitamins online store, one pound jars.
In summary i get the culture from Wards scientific and the F2 nutrient from Aquatic Eco-systems.  Both are on line.  A health food store has the montomorillianite clay.  Wards has micro scales and lab stuff and PH papers.  Aqaurium, heater, air pump at local pet store, and a squeeze pump with tubing for harvesting.  I found 50 micron 4"x8" filter bags on ebay.  The other thing you need is a sunny window.

im kinda confused by the pics. spirulina is a single celled algae. Ive been growing it all winter, with nothing ut a container of fishy water sitting in the sun from a window. Mine grows as green in the water. It gets darker and darker green. Yours seemss totally different.

  I just cant figure out a way to harvest the stuff. Im growing it for phyto plankton. My method has been to let it sit out of the sun for a day or two and it falls to the bottom of the container, then I pour out the water, and have it more concentrated to give to the little plnktons....

   

Spirit,  does the spirulina you grow have the same kick to it as the store bought?

Reading the posts in this topic, I think your setup is slick.  I want the same energy diversity that you have.

Now I also want to grow spirulina.

Silverseed:  The photo showed what I was getting with the aquarium heater running.  When It warmed up I took the heater out and the stuff changed.  Instead of clumping up by the heater it is very fine and disperse.  When clumped I could harvest with a fish net, but no longer.  On ebay I found a sock filter size 4 (4"x8") 50 micron that I clip to the side of the glass.  At petco I bought a bottom vacumn device with a suction tube and a squeeze pump that I lift the algae off the bottom and into the filter.  It takes a couple of minutes to harvest 10 grams or so, that the two of use use daily.  When I tried using a small mag pump it just forced the algae thru the mesh and you couldnt get as much.  My tank doesnt get very green, perhaps I havest to often to let it get dense but I think it just has not gotten warm enough.  The stuff wants 95 deg.F to rally fluorish and mine often falls to 70 and below.  It is located in an unheated laundry room where it can get full sun.
Shawn:  If we take it fresh with just a rinse it has more of an energy kick.  If I harvest early and let it dry on cheese cloth it is comparable to store bought spirulina as sold by NOW herbals.  Fresh it has more of a seaweed taste.

spirit, Im no expert here.... but it might be a lack of nutrients for the algae? I was using fish water sitting in a window of decent sun, it gets COLD there in the night in winter. I had no heat on it. Mine didnt get near as thick as commercial operations, but it got rather thick for sure. a DARK green.

Silverseed:  I use the standard Guillards F2 nutrient at the suggested rate plus montromorillianite clay for max minerals and some urine for PH control.  The F2 is the standard nutrient used by commercial growers.  I had no other starting place and have not been going long enough to experiment.  You should  be able to use fish water or poop for that matter, but remember mine is for human consuption.
During our recent cold spell I returned the heater to the tank and now the algae is clumped up again by the heater.  The whole point of this is to ensure a source of enzeyms minerals and vitamins for us.  We grow most of our food but what if our garden has a serious faliure?  The goat dries up and chickens all die?  If we have to depend on food from the market we will be as sick as everyone else.  Also like kelp and seaweed algae is good treatment for radiation exposure.

  i dont think fish water negates its use for humans myself. aztecs ate it right off of a lake. Its sold commercially off of many lakes and ponds globally. I cam across someone working on a commercial set up to raise it off of fish water from fish farms, and feed it to tilapia, and sell the rest to humans.... and your peeing in yours? Keep in mind the bulk of the fishes waste is gone as the algae grows.....

  if your buying all the nutrients it needs to grow, Im not understanding the point... of course if it works for you thats great....

  since you mentioned emergency situation and growing it.. Im sure you know urine and iron alone will grow it. You can get some iron into water by using a bit of vinegar and a old nail. dont need much at all.

  Its weird how differently ours grows... Im wondering if we have different strains? or one of us was sold something else? either way. either way the bulk of green water plants are as good or nearly so as spirulina. fertilize some water and keep it in the sun, and youll get one in time. the spores travel on the wind. just in case your culture dies, and you want to grow more...
   

It's definitely possible you've both got different strains. There's over 30,000 species to pick from.

I buy from the University of Texas at Austin. http://web.biosci.utexas.edu/utex/default.aspx

I'm using a specialized PhotoBioReactor setup in my garage with radiant heating/cooling and automated lighting cycles and can harvest about a pound a week.

Daerk wrote:
It's definitely possible you've both got different strains. There's over 30,000 species to pick from.

I buy from the University of Texas at Austin. http://web.biosci.utexas.edu/utex/default.aspx

I'm using a specialized PhotoBioReactor setup in my garage with radiant heating/cooling and automated lighting cycles and can harvest about a pound a week.

a pound a week? dang... I could use that for my phyto plankton.... can you explain it some more?

SILVERSEEDS wrote:
a pound a week? dang... I could use that for my phyto plankton.... can you explain it some more?

Sure... I plan on uploading some videos documenting the building of the PBR sometime soon. ish. maybe. ;P

Essentially it's a multiple polycarbonate tube and sched 40 pvc vertical reactor with forced CO2 input via microbubble diffuser at the bottom of each tube, and an airstone pumping fine bubbles of compressed local atmosphere into the tube for agitation of the algae as it's growing. I use the same F2 medium as described above. I use a set of specifically tuned wavelength lights and cycle them via computer for exposures. I use a stepper motor gearbox to oscillate the vertical light shaft for light and shadow play across the tubes (the algae likes it and grows more and faster). I use a radiant heating and cooling tube (externally heated/cooled) to regulate temperatures in each individual culture tube. These radiant temp control tubes are rigid and flexible tubing combinations that thermally leach their values into the grow tubes. Best temp is 86 degrees F constant. I harvest via a manifold system that drains via the base of each tube (ball valve to inverted reducer (barbed) to hose to harvest tank) and I harvest using 50 micron screen-printing fabric on an aluminium frame. The harvested water (with leftover algae) is placed back into the tubes and pre-treated pre-warmed medium is added via a 55 gallon tank and mag pump through a manifold system. At the top of each (sealed, closed loop) tube is an air purge valve to offgas the pure oxygen byproduct and unused CO2.

I'll upload some pics of it in action sometime soon. ish. maybe. ;P

EDIT: This is about a $3,000.00 PBR assuming you build the stepper motor gearing and do all the wiring and sealing and whatnot yourself. The same PBR can be sold for about $12,000.00

  dang... I can do most of that low tech, but not nearly as regulated.... I should put it together sometime, as the same size as your set up and see how productive it would be for comparison.... im going to be growing this for the bottom of my food chain for my fish cultures... to feed lots of moina, rotifers and daphnia and other little things.... I was just planing on cycling fish water into a clearish 60 gallon drum on its side with the top cut out, to get the most surface area out of the container.... with a bubbler. I might have to try co2 as well, with the results you have....

  how do you harvest? I havent found a decent way o harvest... of course this might not be an issue for the raising of the little guys Im raising, but I might use it for anythings if i could harvest well.