Popular in some South East Asian farming practices, Photosynthetic Bacteria (PSB) can be cultivated with only a few basic ingredients. PSB are often the first to colonise a newly expose area of dirt and provide food for other microorganisms. PSB come in a variety of colours. Pink-red strains are considered to be the most desirable, although green and white are also used. Interestingly as time progresses a sample will sometimes change colour as a dominant strain out competes others. It must be said that PSB do not smell nice and in a small suburban garden the sulphurous odour may offend sensitive nostrils. Finding a water sample with sufficient PSB to begin a culture can also be a challenge. You need to look for shallow water that gets lots of exposure to the sun. Ponds and slow flowing creeks are a potential source, but don’t overlook backyard fountains and fish ponds.
Collect water samples from a natural environment. Whisk an egg, two tablespoons of fish sauce, and half tablespoon of msg. Add two tablespoons of the eggy-fishy mixture to a 1.25lt plastic bottle and shake it up with the water sample. Bathe in sun for 2-4 weeks. The resulting colour will depend on what PSB is present and the duration of the sun bathing. Pink and a Green are the most desired colours. Sometimes the colour will change over time as different strains within the bottle become dominant. Diluted heavily before application to the soil.