P, Fe, Cu, Zn, B, Mo, Mn, Na, Cl all have distinct recognizable toxicity symptoms when given in excess in plants such as burned margins and tips, yellow-black necrosis, cupping ,rolling, stunting etc. K and Ca do not but show up as deficenies of Ca and K respectively.
I don't know anything about inverterbrates and other aquatic life.
The recognizable symptoms you refer to have been known and relied on for a long time to indicate certain deficiencies and toxicities. The main thing about them is that they are all based on experiments and studies done a long time ago and may in fact be flawed assumptions. With new technology and added knowledge we may very well decide that they are not correct in reality.
Methods used to demonstrate and index the toxicity levels of the P, Fe, Cu, Zn, B, Mo, Mn, Na, Cl would all have been done with perfect(?) N and K levels as a baseline. They also would not have thought to look at potassium as a possible cause for toxicity or recognized the toxicity symptoms. It may very well be that with low K levels the toxicity of P, Fe, Cu, Zn, B, Mo, Mn, Na and Cl will be greatly reduced.
The real question we should be asking is why do we think plants need to be fertilized with high levels of potassium? The observations that Rick has reported suggest that potassium excess may be showing symptoms that no one has ever recognized...until now.
Potassium toxicity = reduced growth and reduced resistance to pests and disease. ????????????
The truth is that Rick's observations while studying algae (or whatever) may have led to an important new level in the understanding of plant nutrition.
Maybe he will get the Nobel prize? Maybe Rick should have kept quiet? :sob:
Too late!
