The truth on Phosphorus
Phosphorus is an essential element in all living systems, where it is normally present at levels of about 0.3-0.5 per cent dry weight. It is important in cells as a structural molecule (present in phospholipids and nucleic acids), as a major storage component (particularly polyphosphates) and is involved in energy transformations (ATP) essential for all life forms.
Phosphorus is present in the aquatic environment as soluble organic, insoluble organic (lake biota and detritus), and soluble inorganic (fertilizers as phosphate) forms. In most freshwaters, phosphorus occurs mainly within the lake biota as insoluble organic.
Phosphate assimilation of phosphorus by freshwater algae is restricted to the uptake of biological nitrate and phosphate ions, the concentration of which is referred to as 'total soluble phosphate'. Dissolved organic phosphate, the other soluble component, is readily converted to phosphate by phosphatase enzymes, and together with total soluble phosphate, constitutes the 'biologically available phosphorus' within the water. Biologically available phosphorus cannot be determined chemically but must be measured by an algal assay.
Although the requirement for phosphate by freshwater organisms is considerably less than biological nitrate (Redfield Ratio), it is normally phosphate which is growth-limiting in freshwater systems where there is no phosphate or too much phosphate. This limitation depends on the balance between carbon, nitrate as nitrogen and phosphate availability (C117/ N14/ P1). High phosphate levels and a lack of natural carbon from man's need to clear land has led phosphate to become a nitrification inhibitor. TWC Block contains that needed carbon source without releasing the carbon. This gives a controlled structure for beneficial bacteria to produce the needed biological nitrate required to maintain this balance.
Blue Green Algae due to limitations
Blue-Green Algae (Cyanobacteria) becomes the dominant bacterial species when the nitrogen cycle slows due to limitations. It is dealing with the excess nutrient load but it does this at the expense of the healthy ecology as the enzymes it produces in large numbers are highly toxic. Blue-Green Algae (Cyanobacteria) also looks after its self by securing its future bloom. Once it has dealt with the excess nutrient load it dies off creating a thick rotting sludge on the bottom of the waterway which then becomes the next nutrient overload, thus securing its own rebirth.