Will my Spirulina die during shipping? How long can I keep it alive in a bottle, so I can get together my kit or keep a reserve?

Shipping within the continental U.S., we have not had any problems with shipping our starter bottles. We recommend express shipping to Hawaii because the “slow boat” takes over a week, and that it too long for the algae to sit in a sealed bottle in the dark. For international orders involving live cultures, please contact us for more information.

If the bottle is kept with a loosened cap or cotton balls in the mouth so it can breathe, indoors in a bright location out of direct sunlight, it can live for weeks or even months. It can easily survive for a few days in a box or suitcase, especially if it does not experience temperature extremes (less than 50F, more than 90F). I have often flown with a bottle in my checked baggage. It will do especially well if you stir it up as often as you can (once a day is fine), or you can bubble it with an aquarium pump and a little tubing (included with the kit!).

We recommend using only half the bottle to start your first tank, so you can try again if you need to. Once you get your culture going, it’s good practice to put aside a bottle once a month or so, as a reserve in case anything goes wrong with your main culture.

I want to grow using an AlgaeLab kit, obtaining my own algae. Where can I get live Spirulina culture for my kit?

Please contact us if you would like us to ship you live Spirulina outside the U.S. Other sources would be algal culture libraries. The two main U.S. culture libraries UTex (www.utex.org), or NCMA (ncma.bigelow.org , formerly CCMP), ship internationally. In Europe, CCAP (http://www.ccap.ac.uk) or SAG (http://sagdb.uni-goettingen.de) can provide live Spirulina culture. In Australia, contact the CSIRO’s Australian National Algae Culture Collection (http://www.csiro.au/Organisation-Structure/National-Facilities/Australian-National-Algae-Culture-Collection.aspx), and ask for their Arthrospira maxima (strain CS-328). If you can get a bottle of our culture, we do recommend this, as we provide a much larger amount of culture (almost 1 liter) of healthy, multiplying algae, grown in the same exact medium that we sell and give recipes for in our instructions. Also, our prices are much better…

What size tank should I start with? How big can I go?

Our kits work well with 10-gallon aquarium tanks, so this is a good place to start. We like these tanks because they are quite inexpensive ($15 or less), are made of glass and pure silicone — safe materials for contact with food! — and because light penetration is fairly good, so the culture can get thick. In an unshadowed south-facing window, you should be able to get about half a tablespoon (4 grams) every day from such a tank. Community members have had excellent luck, though, with everything from 2 liter bottles to giant fish tanks and even greenhouse-covered ponds. There is no upper limit to how big you can grow; take over your back yard!

How long does it take to grow from the kit with the 1 liter starter bottle, until I can start harvesting from my tank?

Grow-up proceeds in stages — see the instructions; you put half the contents of the bottle into one quarter of the tank (2.5 gallons for a 10-gallon tank) to start with, which results in a very thin culture at first, which will thicken over time. After a couple of weeks, the algae should be thick enough that you can double the culture volume, then after a week or so, double again, so that the tank is full. Once the tank is full, the algae is thick (3cm Secchi or less, see below), and the pH has been at least 10 for 24 hours, you should be able to harvest. This process can take from 3 to 6 weeks.

How can I grow Spirulina organically?

Our nutrient mixes use pure, food-grade nutrients that are entirely water-soluble. Growing Spirulina using only organic fertilizer is challenging because most organic fertilizers (manure, compost, etc.) are largely insoluble in water. Extracting nutrients from such material, and purifying them so that only the desired nutrients are present in your culture, is a rather advanced topic, beyond the scope of most starting algae farmers. We may teach more about these techniques in the future.

Do I need starter culture? If I just add nutrients to water won’t algae grow “spontaneously”?

We grow a very specific strain of Spirulina algae, Arthrospira platensis, that has been extensively tested both for safety and health benefits. If you just add nutrients to water and wait, some algae *may* grow eventually, but it almost certainly won’t be Arthrospira platensis. Many species of algae produce toxins, so it won’t be anything you would want to eat!

Can I harvest multiple times? How do I use the Make-Up Mix? What supplies will I need over the long term? What is their shelf life?

Once you have a thriving culture (which typically takes a few weeks), you can harvest from it regularly (how often depends mostly on how much much light they algae get, the more the better); each time you harvest, you add a little Make-Up Mix to the culture to make up for the nutrients that are taken out in the harvested algae. Every 4-8 months, it is necessary to replace the medium to keep growth rates high (see below for more details). This requires Starter Mix and Iron Solution to make fresh medium. Complete recipes are included with the kits and culture bottles. We don’t know the exact shelf life of our mixes, but if kept in their containers it is likely to be years if not longer.

Are there any concerns about contamination, or other organisms growing in the tank?

Spirulina are very special in that they thrive in a very alkaline medium, at a pH of about 10.5. Very few other organisms can grow or even live at such a high alkalinity and pH, and this generally keeps other algae, or other potentially harmful organisms, from growing in your system. However, it is still important to cover your tank, and keep extraneous materials, insects, etc. from getting into the culture. Commercial spirulina is grown in outdoor, open ponds, where they are constantly exposed to potential contamination, and rarely have problems. If you cover your system and protect it from contamination you should be fine; that said, don’t eat your algae if the pH is below 10, or if there is anything unusual about your culture — the color is off, etc. We also strongly recommend getting a microscope (400x) and looking at your culture frequently – it’s a good way to monitor their health and to be sure the culture is pure…it’s also just plain neat to see the spirals you are growing!

What strain of Spirulina are your cultures, and where does it come from?

Our cultures are Spirulina platensis, more properly known as Arthrospira platensis. This is probably the most commonly-grown strain grown for food. The original cells were taken from Lake Chad, in Africa, where the locals have a tradition of eating wild-harvested Spirulina.

Why the focus on Spirulina? Do you help with growing other types of algae?

We do have experience growing other types of algae, including Chlorella, and support those who want to grow them through our workshops and online trainings. We recommend Spirulina as an excellent introduction to algae farming for three main reasons: it can be grown in a medium excluding other organisms (see above), it is very easy to harvest, and the harvest stuff – live, fresh Spirulina – is highly valuable (better than the powder, and cannot be obtained any other way), and is good to eat immediately after harvesting with no other processing. This makes it about ten times easier and safer to grow, and ten times more rewarding, than any other algae, at least for beginners…

Can you help me make biofuel from algae?

Yes, we can! We do suggest starting with Spirulina, though, as the best way to get started growing algae is to grow Spirulina, as it is inherently easier and safer to grow, for the reasons described above. For help with growing biofuel strains, harvesting them, and processing them into products such as biofuel, come to our workshops and online trainings. At this time we do not sell kits or culture for biofuel, though we may do so in the future.

Why do I need the harvest cloth? Can’t I just drink the algae water?

You should not drink your culture! Although the ingredients are technically food-grade, they are plant nutrients, not human nutrients, and the high alkalinity of the water can upset the pH of your system and give you a case of the “runs”! Also, you want to re-use the water, after you have filtered out the Spirulina spirals using the harvest cloth, so you can grow more Spirulina in it, as it still contains valuable plant nutrients. This is also why growing Spirulina uses so little water – the water is well contained, and is recycled many times.

How much Spirulina will I be able to harvest from my tank, how often, and for how long?

If you follow the instructions and thus provide proper temperature, pH, and nutrients, yield will depend mostly on the hours of bright light the tank receives. This generally means sunlight. (See below for a discussion of artificial lighting.) In a south-facing window with plenty of direct sun exposure, you can get roughly a tablespoon of live Spirulina harvest from a typical 10-gallon tank every other day.  Two or three such tanks (or bigger) can fit in a window for daily harvest.

For how long? If the proper amount of make-up mix is added back to the tank after every harvest, the nutrient balance can be maintained for a high level of growth for about four to eight months, at which point the pH will have risen too high (11+) for good growth.  At this point you simply mix up a new batch of medium, harvest all your Spirulina, and immediately put them in the new medium.  After a couple of weeks your culture should be full, dense, and ready for harvest again, ready to start the 4-8 month cycle. So, you need enough starter mix to renew your culture every 4-8 months, though it’s a good idea to keep some on hand in case anything else might go wrong with your medium (though this is unusual).  There is no reason why you shouldn’t be able to keep going this way indefinitely.

The recipes for the starter and make-up mix are in the instructions if you want to make your own.

How do I use the Make-Up Mix?

As described above, the make-up mix is used only at harvest time (or when removing dead algae).  Add an amount of make-up mix proportional to the harvested algae – one teaspoon of the mix per tablespoon of harvested algae, plus a dash of iron juice.  This makes up for the nutrients lost in the harvested algae, thus the name.

How do I keep my  Spirulina alive when I go on vacation?  Can they be “parked” for a while?

The trick is to slow down their metabolism by lowering the tank temperature. This can be done simply by turning off the heater.  The tank should also be kept from strong direct light during this time as well, although it does need some light.  If kept in this way, it should be fine for several weeks or more.  When bringing it back from this state, raise the temperature and light in stages, over a few days, and the algae will be fine.

Can I use artificial lights to grow my algae?

Some algae-nauts have had good results from using artificial illumination, but it’s worth remembering that direct sunshine is about 100x brighter (~100,000 lux) than the light in what would be considered a very well artifically-lit room (1000 lux).  It’s hard to compete with the sun.  If using artificial lighting, it’s smart to take advantage of the heat generated by the light fixture as well, as in the used by one AlgaeLab-er, where fluorescent bulbs are inside jars (formerly spaghetti jars) immersed in the tank.  See below for a discussion of the optimal color for an artificial light source.

Do I need to tell you to be very careful about combining water and electricity?  Watch for dripping water going along power cords – keep plugs high so you won’t get shocked!

What are the health benefits of eating Spirulina?

Too many to mention here; take a look around the Web for a more complete picture.  In a nutshell, because it lacks a cell wall or any other indigestible components, Spirulina is a super-concentrated, highly available nutrient source, which enhances the nutrition of any food eaten with it.  Spirulina is about 65% complete protein, and the remainder is packed with anti-oxidants, essential omega-3 fatty acids, and other compounds with healthful anti-inflammatory, anti-viral, and anti-cancer properties.  As a blue-green algae, its nutritional value is unique, since blue-green algae split evolutionarily from green plants approximately a billion years ago.  My experience with Spirulina (I eat about 15 grams a day) is that it greatly improves my stamina, raises and levels out my mood, and speeds up all kinds of healing.  The first two effects are consistent with clinical studies that show a large reduction (up to 50%) in the glycemic index of foods eaten with even a small amount (2.5%) of Spirulina.

Is live Spirulina better for you than the powder or pills I can get at the health food store?

All studies of the health benefits of Spirulina have been on the dead, powdered stuff.  It stands to reason, though, that the live, fresh version of such a highly perishable food would have superior properties, and this is my experience, having eaten both.  Purveyors of the powder claim that they take every precaution to preserve the nutritional properties of the algae, but what would you rather eat, a fresh blueberry, or a powdered blueberry?

How long does the live, fresh Spirulina last?  How can I preserve it?

Fresh Spirulina, once removed from the preserving alkaline environment of the tank, is like raw eggs in its perishability – it should be eaten or refrigerated within an hour or so of harvest.  It will last in the fridge for up to three days. If frozen, it lasts indefinitely; if dehydrated (and kept dry), it will last for about a year, longer if kept in an airtight container.  It’s not hard to tell if it does go bad – it smells like rotten eggs.

Is there an optimal artificial light to use for growing Spirulina?

As a general rule, a plant or alga (or anything else for that matter) absorbs the wavelengths (colors) that are not present in its apparent color, which is made up of the wavelengths which it bounces out without absorbing. So, the chlorophyll of green plants absorbs mainly red and blue light, and bounces out green light. Green plants need both red and blue light to thrive. Blue-green algae, such as spirulina, have special accessory pigments called phycocyanins and allophycocyanins, which allow them to capture more red and orange light (and to a lesser extent yellow and green) than green plants. They do have chlorophyll (only slightly different from green plants’ chlorophyll), so they also use blue light.

For these reasons, ordinary “grow lights”, which are optimized for green land plants, are not particularly good for growing Spirulina or other blue-green algae (though they will work). A light with more red and orange light — i.e. a “warmer” color — would be more efficient for growth, as a higher fraction of the light will be absorbed. Another approach would be to use white light supplemented by a red-orange light source (peaking at 620-650 nm), to hit the phyco-pigments better. I have used the “warmer” colored compact fluorescents with some success, but haven’t done any side-by-side testing. In general, though, the color of the light source is not as important in my experience as getting the nutrients and temperature right, and providing LOTS of light, which is a lot easier using sunshine!

My source for information about the pigments used by Spirulina is Vonshak’s excellent book Spirulina Platensis: Physiology, Cell biology, and Biotechnology.
You can also check out Wikipedia:

How big would the setup need to be in order to create about 100gm of spirulina each day?

To grow 100g of Spirulina a day would take roughly 20 square meters, or 216 square feet. It would have to get plenty of sun. If you set this up outdoors you’ll need to take into account the increased risk of pond contamination, so you’ll have to be much more vigilant about monitoring your culture — get a microscope and check your culture every day. If you see anything besides Spirulina spirals, don’t eat it!

I have an old swimming pool/hot tub I am not using. Could I convert it into a Spirulina pond and grow in quantity?

You can, but you’ll need to mostly fill it in. Commercial Spirulina production ponds are never more than about a foot deep, because otherwise the culture on top will unacceptably shade the Spirulina below. Using a lot of circulation can help matters somewhat, but the density of the culture will be lower the deeper the pond is. The amount of Spirulina you can grow is determined by the surface area exposed to sunshine, *not* the volume of the culture! Also, in an outdoor setup there is much increased risk of pond contamination, so you’ll have to be much more vigilant about monitoring your culture — get a microscope and check your culture every day. If you see anything besides Spirulina spirals, don’t eat it!

What’s a good method for determining algae harvest time – how do I know my culture is ready to be harvested? Is there a good method for determining growth over given time?

The best thing is to print out a 2×2 black and white checkerboard pattern on a square 2″x2″, seal the whole thing up with clear packing tape, and attach it to a piece of wire that has centimeter marks on it. Or buy the “pro” version. If you don’t have a printer, use something white in place of the checkerboard pattern. Then you can stick it in your tank and see at what depth it “disappears”. It is a surprisingly consistent and useful measurement.

My culture is forming foam at the top! What is going on?

This is generally because you are using too much aeration. Your bubbler only needs to keep the culture rolling (not moving more than a foot or two a second), no more… Most of the gas exchange (carbon dioxide in, oxygen out) occurs at the upper surface, not on the bubble surface, so the idea is to get the culture up there often through circulation, rather than by forcing in maximum bubbles.

Where does Spirulina grow naturally? Can I grow them under “natural” conditions so that cultivation will be less work?

Although there are many strains of Spirulina, the ones used for food are found in natural soda lakes in warm climates. These strains are quick-growing in extremely high pH and alkalinity environments, which tend to exclude potentially harmful organisms. Keeping the culture pure, though, and getting good growth consistently requires quite a bit of attention, which is why it is better to grow intensively in a smaller area, rather than letting nature takes it’s course. Also, I don’t recommend growing in outdoor ponds of any kind unless you are extremely vigilant about monitoring the culture for pH (which should be 10+ if you are going to harvest), and for other organisms – i.e. get a microscope of at least 400x and use it to check the culture every time you harvest.

What temperature range is best for Spirulina?

Spirulina grows best when warm — over 80F. Its peak growth is generally in the mid-90’s. Above about 102F will kill your culture quite quickly. Temperatures below 60F will also harm, though usually not kill, a Spirulina culture.

Can you eat too much Spirulina?

Some people say so, though as far as I know the research necessary to ascertain the maximum safe dose has not yet been carried out. Spirulina has been extensively studied for toxic effects in animal studies, including doses (800mg/kg) equivalent to giving 60g dry powder to a 165 pound person, and replacing up to 60% of protein intake with Spirulina, with no ill effects. In hundreds of clinical studies of the effects on people of eating Spirulina, no negative effects have been found. Although bad effects from large doses of Spirulina cannot be ruled out, I can say that I have been eating 20+ grams a day for three years now, with only positive effects (that I know of!). However, this is considerably higher than the doses used in clinical studies, and I would not recommend eating more than 5 grams a day without consulting a physician.

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