Growing Spirulina: A How-To

The idea of consuming spirulina, let alone growing your own, might be off-putting. But hear me out: spirulina is widely considered the most nutrient dense food on the planet. With high levels of protein, B-vitamins, antioxidants and other nutrients like copper and iron, spirulina is like the whole foods version of your daily multi-vitamin.

But, at close to 50 cents per serving, it’s certainly not what you might consider economical.

So what can you do instead?

Grow your own, and here’s how:


  • Fish tank
  • Harvesting materials (sponge, cheese cloth/strainer, etc.)
  • Spirulina seeds
  • Culture (water and food for spirulina)
  • Racks for drying harvested spirulina
  • pH tester


  1. Set up your tank in a location with sufficient light. Spirulina requires light for proper growth so a spot next to a bright, big window is best.
  2. Ensure that your tank is aerated to allow for sufficient oxygen and growing conditions.
  3. Check the temperature. The optimal range for growing spirulina the fastest is at a toasty temperature between 95-98 degrees Fahrenheit, although a more moderate temperature of 64 degrees Fahrenheit and above will also work.
  4. Monitor the pH of the tank.
  5. Fill your tank with filtered water.
  6. Use a proper culture, such as this one, to start your spirulina off strong. Mix with spirulina seeds. Follow the instructions as directed by your particular culture medium.
  7. Harvest after 3-6 weeks. The algae will be thick.
  8. The hardest part is ensuring that the algae removed is just algae, and not entirely liquid. There are several harvesting devices available online. Consider drying your spirulina on drying racks for later use, or consume it fresh, when the highest amount of micronutrients are available.

For more information and a how-to guide, check out this link here. Happy spirulina growing!

Photo Credit: "Bubbles" by Brad Smith is licensed under CC BY 2.0