I think the FA was flushed but the WH reacted more to a strong influx of nitrogen. Before the flood the WH were headed downhill condition-wise as FA was going crazy due to high phos levels I believe.
The reason my arrowhead are showing signs of stress (I believe) is because I'm pumping all of my nutrients out watering grass. They are suffering just as my WH did. Once the nitrogen was back, things (plants) greened back up but samples showed my phos was still low and the FA never came back.
I believe I'm going to try fertilizer tabs directly near my plants, or maybe just select plants to see if there's a direct relationship there, which I'm sure there is but to what level I'm unsure.
I do know that areas with frequent rain from storms with little if any lightning has very low nitrogen present and just the opposite in strong, intense lightning storms, rain is much higher in nitrogen.

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