Potassium Phosphate contain two of very important macro nutrients for healthy plant grow. They are know as macro nutrients because plants uptake for those nutrients is much more then trace (micro) nutrients.
Phosphate (P) is one of the most important macro nutrients for plants grow.
Good level of Phosphate also prevents GSA (Green spot algae).
Phosphate deficiency symptoms
Older leaves yellow and part of the leaf is reabsorbed leading to death patches. The leaf falls off rather quickly. GSA (Green spot algae) forms on old leaves.
Plants requirements for healthy grow
Carbon (supplied as Carbon Dioxide CO2)
Trace elements (micro nutrients)
Store in a cool, dark place