For slow or slowing eutrophication of your water feature regarding phosphorus, I really like the insightful summary by 'rivershed':
Quote
50 ug/L is 0.05 ppm, which is commonly quoted as the lowest value that is safe from the process of eutrophication. So the answer to my question seems to be: if you see any phosphorous in your water with any hobby test, it's probably too much.

Last edited by Bill Cody; 07/06/24 01:00 PM.

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