It took me some time to gather all the stuff I needed but my small indoor algeafarm is now up and running.. I constructed a box from insulationboard and mounted a fluorescent growlamp inside. To fully use the light, and heatloss, of the growlight I lined the inside of the box with aluminiumfoil. The growlight is controlled by a timerswitch on a 16/8 hour light/dark cycle. With just the growlight, the inside temperature of the box reached to about 25°C. For optimal growing conditions Spirulina likes it a bit warmer so I added a propagator heatmat in there. Now the temperature is around 33°C wich is perfect.
I had some issues with preparing the Zarrouk grow medium. The base for this medium is distilled water but I thought I’d give it a go with just plain tap water… Turns I couldn’t dissolve 17grams of soda and bakingsoda in tap water. The final solution looked like some milky water so not all the salts were disolved. I tried to add some algea to that mix but after a few hours all the loose salts and the spirulina had binded together in one clump. So I went to the hardware store for some deminerelised water and started over. This time it worked and the growmedium looked clean. I prepared 500ml of growmedium and added 150ml of culture from my ‘motherbottle’. Today, about 36 hours later the seem to be multiplying quickly. The bottle looks a lot greener.