Growing algae to replace fossil fuel oil was all the rage in 2009. Unfortunately, large scale production of algae can be a complicated process requiring careful nutrient monitoring to avoid crashing the reactor. However, growing algae on a small scale for DIY projects can be achieved using off the shelf controllers and sensors. We are going to briefly review three different DIY Photobioreactors in this post all of which have solved the basics around sensors, temperature control and lighting. Once a successful photobioreactor has been constructed the applications it can be applied to are numerous.

Here are some of the typical uses:

growing chaetomorpha algae for aquarium nutrient management
chlorella and spirulina for as nutritional supplements (high in protein and vitamins)
exotic high value cultures like astaxanthin which is worth more by weight than gold and popular to color farmed Salmon pink. Also commonly used as an anti-inflammatory supplement for people with arthritis.
bioremediation
genetic engineering
space research – absorb CO2 and be a food source

reef-pi

reef-pi is an aquarium controller that is arguably Adafruit’s most EPIC set of guides (7 parts total). This seven part guide has all the essentials for an advanced aquarium setup or algae photobioreactor. The project is controlled using multiple Raspberry Pi modules. The following can be automated using the reef-pi hardware:

pH
Temperature
Water level
Lights
Nutrient dosing

BioMONSTAAAR

This open source bioreactor has been made available through Instructables and uses a Pi for the primary data collector, but relies on some Arduino components for the sensors and actuators. This is another very meticulously documented PBR.

Pressurized Algae Photobioreactor

This last DIY reactor takes a different approach using a bicycle pump to create a pressurized environment. The final assembly based on a 4.2 gallon plastic carboy is lightweight and somewhat portable. It looks pretty good, but does not compensate for temperature.