I found Dinoflagellate & Coral work together to fix nitrogen in water for plants. However, it live mostly in salt water conditions. Cyanobacteria is one of the first bacteria to fix nitrogen, but it needs at least three things for it to grow, decay of organic material, bicarbonates in the water and light. If we wanted to reduce the number of fish in our tanks, it is possible to have the fish eat some of the Cyanobacteria (its close relative is Algae). We still need to have some sort decay to feed the Cyanobacteria.
I see it as a new avenue for cost reductions in vegetable productions for industrial systems. The problem I came across while trying to select the strain of Cyanobacteria is the Agar recipe. It gets very involved. The recipe is not simple dextrose or other house hold things.
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