In Part I we built a simple home CO2 scrubber using algae. I'm writing this instructable to demonstrate how to culture and cultivate algae using more or less laboratory style procedures but substituting some readily available items for more traditional laboratory glassware.
I encourage you to experiment and understand how to successfully cultivate algae. The techniques and process outlined here will work for most algae strains.
Please bear with me, this is a work in progress. I normally publish open source software where the policy is "Publish early and often". The content is constantly being revised and I'm open to collaboration on many elements.
For instance the crude incubator could easily be supplemented with a sound design using plastic sheets with hinged access panels and portholes with oversized rubber gloves mounted in them. And so on.
In Part I we used a readily available algae source to create a healthy algae culture which gets fed with air, sunlight and liquid plant food to provide CO2 scrubbing on a small scale.
The original sample probably had a wide variety of micro-organisms, many of which are probably bubbling harmlessly away in the soup. But we're not here to create bio-soup, we're here to make algae.
It will be very nice for you if you have a microscope but you do not need one. It should be possible to obtain a single species algae culture and breed it up to production reactor populations without one. If you happen to have one, as I do not, then you can whole hog nuts and breed a pure culture from a single cell.
In any event if you want to get serious about algae you'll need to learn to culture and cultivate algae. These skills can be applied to special purpose algae species obtained from the appropriate channels. There is an appendix with more detail on obtaining single species specialized algae cultures from universities and research institutions. Expect to pay about $75 for a culture which, with sound breeding practices, is sufficient to create pure feedstock. Put some of that in a bioreactor full of pure water, nutrients and you're done.
For the rest of us we're going to isolate some algae cultures from our birdbath sample in a Petri dish (or substitute such as I use) with Agar (or a substitute).
From that we're going to identify some single culture strains (one batch of green stuff). We're going to multiply those strains in some small bottles to understand the process of scaling up a culture.
At the end we're going to create our production breeder reactor which will consist of one culture reactor which is used to maintain a constant population and two breeder reactors used to create feedstock for production reactors (in the case of CO2 scrubbers) or for feeder reactors which are moderate sized (3-5 gallon) reactors for producing feedstock for above ground pool based open pond or vertical growth closed reactor systems.
Okay with all said and done let's take a look at what we're going to need...
Step 1: Bill of Materials
1 case Ball brand Mason jars - If you're going to breed algae you're going to have a variety of strains to nurture at various stages. Just do yourself a favor and get a case of the quart size. There is also a very handy half gallon size which is suitable for larger cultures.
A lab journal for recording strains, experiments and results.
Several .5L clear plastic water bottles, labels removed and run through the dishwasher.
A couple of 6+ inch pieces of reasonably stiff wire, picture hanger wire isn't stiff enough and coat hanger wire is the worst case because it's hard to bend but will do.
Calcium Carbonate - Chalk or 500 mg Calcium dietary supplement made from calcium carbonate
Some soil to use for preparing algae media. Should be good rich soil from a variety of sources.
There is nothing special about the particular soil used However, several considerations are probably important, including the following:
1. The soil should be a loam, with a mixture of particle sizes (sand, silt, clay).
2. It should contain a moderate amount (15 - 20%) of very-well-decomposed organic matter.
3. It must not contain pesticides, especially herbicides.
4. It should be soil that has been aged (preferably for 6 months or more) under moist conditions and not, for example, fresh potting soil, soil that contains fresh manure, or soil to which a commercial fertilizer was recently applied.
5. A slightly acidic soil derived from granite or other igneous rock is preferable to soil obtained from calcareous soils.
6. Particulate matter in the soil such as gravel, Perlite, or vermiculite are not necessarily damaging but can be of considerable nuisance when wishing to quantitate the amount of soil used in the medium or when handling algae that are physically associated with the soil. Particulate organic matter, such as compost that is only partially degraded, should be avoided "altogether.
Aluminum cake pan for heating and foil to line it. 2 quart pot with cover for boiling.
6 Petri dishes (see picture) or a reasonable substitute. Most scientific supply stores will offer prepared dishes with Agar. If these are available use them.
Almost any shallow, wide mouthed container that can be easily covered with Saran Wrap(TM) and sealed with a rubber band will do
I will be using baby food jars with the labels removed.
Glassware will need to be cleaned thoroughly or sterlized between uses.
At minimum place them opening down in the dishwasher and when removing them after the cycle completes keep them upside down until the cap is screwed on. Keep the cap inverted until just before closing the bottle. This will minimize accidental contamination.
A couple of gallons of fresh water will do nicely. Its probably worthwhile to pick up one of the 3 gallon bottles of fresh water available at the supermarket. Especially if you're thinking about any sort of small volume production you will need several of these for use as feeder reactors.
Materials to build the culture incubator. This will be used to breed algae at various stages as we reduce the population samples, then incubate the targets and attempt to get identifiable algae strains. It is not strictly speaking necessary to use an incubator for the hobbyist. For anyone who is serious about cultivating algae and plans on obtaining cultures of more exotic algae from scientific and academic supply houses an incubator is probably appropriate.
20 gallon aquarium (does not need to be watetight)
Heavyweight clear plastic
The side from a zipper plastic blanket bag my wife had
Plastic garbage bag would be okay. White is best
Small lamp that can use up to 75-watt bulb
Bulb size will vary based on desired temperature
On/Off electrical timer set for 18/6 on/off cycle
Thermometer (preferably in a clear plastic case)
If anyone knows of an inexpensive temperature controlled thermostat I'd be pleased to hear it.