Introduction: Food of the Future: Window DIY Spirulina Superfood
Having your own spirulina window farm is one of the easiest most satisfying things you could ever take on. It is an environmentally friendly way to produce and consume a complete protein and nutritional source! Algae Spirulina is 25 times more efficient per squared foot than any other plant, which makes it optimal for indoor growth. Integrating algae into our homes can be one of the most significant things that can impact our nutrition. It is truly the food of the future as it contains all of the amino acids and is a complete protein!
Step 1: Hardware
To grow Spirulina at home you are going to need some hardware to optimize and automize the process. Most of it is readily available at your local pet or fish store.
10-20 Gallon Aquarium Tank
Air Pump
Heater
Air Line
Bubble Wand
Thermometer
Food Grade Harvesting tube
Ph Strips
Bi Valve
Harvesting Cloth (50 micron filter cloth)
The only thing that you will need to get from a specific source is your initial spirulina culture. SpirulinaSystems.com is the most affordable source.
Step 2: Tank Setup
Find a south facing window for your tank. You can either use a table to place tank, or you can place a piece of wood on the window sill to make a shelf for the tank. Place tank on top. You can also grow spirulina in a greenhouse!
Step 3: Hardware Setup
Step 4: Medium
The growing medium is the water solution that spirulina can grow best in. Since spirulina grows in alkaline environments, you have to make your water alkaline. This can be done by adding 16 grams/liter of sodium bicarbonate to non-chlorinated water along with other nutrients: Ammonium Phosphate, Sea Salt, Potassium Nitrate. The most important of those is of course the sodium bicarbonate that creates an environments that resembles the ash lakes in nature in which spirulina grows.
To simplify the process, you can buy these nutrients pre mixed like I did. Again, SpirulinaSystems was pretty affordable.
2.5 Gallons of non-chlorinated water along with 1 of a cup of pre-mixed nutrients is the recommended amount to start the culture.
Step 5: Adding Your Culture
Once your starter powder has dissolved and your water has reached room temperature or higher, you can now add spirulina to the medium. Adding spirulina to cold water can shock it, its like taking a cold shower! Only pour in 3/4 of your bottle so that you may have some in reserve in case anything happens to your first culture!
Step 6: Mark You Water Level
A simple step to record your water level is to use a book mark. This is used because water naturally evaporates so you need to replace the water that evaporates periodically.
Step 7: Cover Tank
Adding a glass or plastic cover can decrease the amount of evaporation and help keep in the heat at night. This will also prevent contamition from any airbourne organisms.
Step 8: Adding Iron
At this point you can add Chelated Iron. It completes the nutritional needs of spirulina. Iron deficiencies are noticeable, just as they are in plants. Slight yellow shade is an indicator of iron deficiency.
Step 9: Growing Period
This is where spirulina will begin to use the sun, CO2 from the air and the nutrients you added! Its nice to know that CO2 sequestration helps the environment AND it feeds your spirulina, which will feed you! In a time lapse anywhere between a few weeks and a month, it will begin to get more populated.
Step 10: Repeat
Repeat the previous steps to double your culture: Add another 2.5 gallons with Starter and Iron. Do this until your tank is full. If your culture is a good performer you can add 5 gallons at a time! Once your culture is well populated it replicates far quicker. In ideal conditions, it replicates (doubles) every three days! Much faster than most plants and it can do it year round!
You can now officially can call yourself a spirulina Farmer! Take a moment to understand the monumental significance of this! Spirulina superfood is being produced in your own home in an environmentally friendly way that does not require transportation, excessive water, and does not create runoff like most commercial plants! A pat in the back is well deserved!
Step 11: Harvesting Safety
You are just a few steps away from easy harvesting. Over the last two years of research and development, I have been eating spirulina with healthy outcomes. To replicate that, you just need to follow simple steps. Spirulina has an advantageous characteristic that allows it to grow in highly alkaline environments, meaning pH levels of 10 and above. This dramatically decreases the chances of foreign organisms growing your culture because they just can't survive in that kind of alkalinity. To safely harvest you simply have to wait for your culture to reach an approximate pH level of 10 using readily available pH strips.
Step 12: Harvesting
Once at the safe pH level you can set up your Integrated Harvesting Tube. It is important to only use a material that meets FDA standards because you want to use safe food grade elements in your spirulina farm. I got my kit from Spirulinasystems.com.
Once you open the valve leading to the harvesting tube, fluid should begin to rise and flow.
You can now tie your harvesting cloth to the end of the tube with a rubber band to catch the spirulina flowing through the tube while letting the clear medium flow back into the tank. It is recommended to harvest 1/3 of the culture to allow it to repulate within a day or two. This way you can continually harvest as long as you keep feeding it nutrients.
Step 13: Enjoy
Step 14: Feeding
As the spirulina grows, it consumes the nutrients you added. You simply need to add nutrients. For every tablespoon of live spirulina harvested you need to add a teaspoon of the following nutrient mix. Here are the weights to make one batch of mix nutrients: 1.4 KG of saltpeter, 50 grams of ammonium phospahte, 30 grams of potassium sulfate and 20 grams of epsom salt. Add a half dripper of Chelated Iron for every few tablespoons harvested. Thats it.
Step 15: Quality Control
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161 Comments
9 years ago on Introduction
Hi, this is an amazing instructable to see and I find it an exciting project to want to do.
I'm moving to my own place in just over a month for university and that means I'll have a perfect opportunity to try this out, on top of the fact that it will be an ideal source of nutrition to me when living on the limits of a student budget!
But I have a couple questions-
1: What does it taste like? I would eat even if unpleasant, I just want to know what to expect.
2: Is it infinite? You described having to wait for the PH to go neutral before harvesting so we are able to eat it, but then do you have to harvest it all in one go before it dies/ goes off, and eat in a set period of time?
Or is it more of a case that when you feel hungry just harvest a small batch to eat and as long as you don't have too much each day it will grow back and potentially never run out?
I look forward to seeing recipes too :D
Reply 9 years ago on Introduction
Hey!
Man I wish i had this stuff back in my college years, definitely would help with the late nights and energy needs. You're right on the dot about it being an ideal nutrient source, all you would really need is some calories to burn on top of the spirulina.
Taste: no taste with creamy texture, but added to smoothies or lime water and you will not even be able to taste it. ill add both recipes soon.
Infinite? yes, you harvest 1/3 of the culture and let it repopulate before you harvest again, the next day or so. Just feed it and the water usually lasts about six months before you change it out. will post feeding and maintenance instructions soon
If you had two of these tanks in your room you would be able to harvest a tablespoon a day year round, but you can be efficient and actually stack three tanks in a single window to really up the production.
Reply 11 months ago
Hello Algaescientist. I applaud you for putting in your energy and time into making this instructable.
What is the ideal source of calories to pair with spirulina?
Question 2 years ago
What are the exact dimensions of the rigid (plastic?) harvesting tube?
Thanks!
9 years ago on Introduction
when i looked into this i found that all the indicators to test ph at around 10 were badly toxic so seeing you put the paper into your tank like that was a surprise .
have also wondered for a long time if spirulina would actually grow from the contents of a powder capsule.
so the actual composition of the nutrients is a secret? i no please post details.
Reply 9 years ago on Introduction
plain and simple: what ph indicator are you using?
what are the actual weight composition and i guess percentage of each nutrient. so that we can make our own.
Reply 9 years ago on Introduction
Of course you can get the recipe so you can make your own:
Medium Recipe:
16g/l baking soda
2g/l saltpetre
1g/l sea salt
0.1g/l ammonium phosphate
1 dropper/Gallon of Chelated Iron
Reply 2 years ago
Hello is this 16g/l or 1.6g/l thank you.
Reply 9 years ago on Introduction
more questions talapia ponds are supposed to contain lots of spirulina which is the talapia main foods. so if you take a sample of pond water and hit it with the sodium bicarbonate you should then get only spirulina growing in it?
bought one of those usb microscopes to hopefully see the spirulina in the pond water but got an indeterminate result. so what magnification do you need to determine absolutely that you have real spirulina in the sample? was going to try the wash and split to pure culture theory. yes there is no spirulina culture supplier where i am.
Reply 9 years ago on Introduction
In theory, yes it should be the only one if you actually do have spirulina in the pond.
I have access to high magnification scopes, 400x is the minimum to see cell outline. at 1000x you can see the cell structure.
Reply 9 years ago on Introduction
I have not come upon any toxicity concerns for pH strips used for aquariums. You can actually make your own organic pH indicators (recommended).
Here is the link:
http://www.erowid.org/archive/rhodium/chemistry/equipment/ph-indicator.html
6 years ago
Thanks for this instructable! Just began collecting everything to start my own farm, but one thing is pretty unclear to me - chelated iron. Could you please write what sort of it do you use?
I found many different brands and forms (fertilizers for different sorts of cultivation, for humans) with different concentrations, addons like nitrogen, and so on. And even more confusing is that most popular medium for Spirulina (Zarrouk’s medium) uses EDTA, but I found out that for different pH you need different sources of iron: for pH lower than 6.0 EDTA is ok, but for pH 6.0–7.0 you need DTPA or HEDTA, and for pH higher than 7.0 you need EDDHA or EDDHMA. That means Fe-EDTA is not a best source of chelated iron and yet they use it. Do not want to experiment at the very beginning...
Reply 4 years ago
"EDDHA chelated Fe is most stable at soil pH greater than 7"
Greater than 7 is pretty vague. EDDHA is highly soluble even in high pH <10 and for that reason is a superior source of Iron. I've seen some formulations use Iron citrate and that's pretty ineffective above ~7.5pH. Dunno why they still do it but anyway - Here is a very useful graph: https://manicbotanix.com/wp-content/uploads/2016/04/iron-chelate-soil-graph-web-opt.png
Reply 6 years ago
It's my understanding that Spirulina uses atmospheric nitrogen. I haven't heard of it utilizing nitrogen in solution.
Question 4 years ago on Step 14
"Here are the weights to make one batch of mix nutrients: 1.4 KG of
saltpeter, 50 grams of ammonium phospahte, 30 grams of potassium sulfate
and 20 grams of epsom salt. Add a half dripper of Chelated Iron for
every few tablespoons harvested. Thats it."
Is that correct? 1.4 KG of saltpeter?? I'm pretty sure that's overkill for the KNO3. Maybe you mean 1.4 KG of sodium bicarbonate and forgot the KNO3 by mistake?
4 years ago
Question 4 years ago
Hi Sir
I'm planning to purchase Veg- Omega 3 supplements which are made from fermentation based microalgae. Would you please throw some light in this so that I'll plan accordingly to go for this.
5 years ago
Hello
Thanks for the Tutorial !
The harvesting pipe you use it only to recolt or is always on?
6 years ago
Excellent. Thanks for giving a way to get started.
9 years ago on Step 13
hahaha gross. Technically its uber beneficial but I think most people wouldn't eat it. Great and well detailed article 10 thumbs up :P