Bandit01
03/23/2010, 02:56 PM
Using the Hanna Low Range Meter should one divide the result by 3 to get just the P ? or are we concerned with PO4 ?
I've read and read on this and still don't understand.
I've quoted Randy below and understand it. But I still can't find which we care about. Or rather which one everyone talks about when discussing "Phosphate" levels.
"ppm phosphate-P is just a different unit of measure than ppm phosphate, but it is measuring the same thing, like feet vs meters. Phosphate counts all of the weight of the P and 4 oxygen atoms, while phosphate-P counts only the phosphorous atom in it, and so read lower.
I discuss it here:
The Units of Measure of Reefkeeping
http://reefkeeping.com/issues/2005-08/rhf/index.php
from it:
ppm-P (part per million phosphorus)
ppm-P is a way to measure total phosphorus atoms in solution. It is equal to the ppm concentration of phosphorus atoms, regardless of what chemical form they take. It is often used to describe the concentrations of phosphorus in dissolved inorganic phosphate, dissolved organic matter (DOM), particulate organic matter (POM), or total organic matter (TOM) in seawater."
I've read and read on this and still don't understand.
I've quoted Randy below and understand it. But I still can't find which we care about. Or rather which one everyone talks about when discussing "Phosphate" levels.
"ppm phosphate-P is just a different unit of measure than ppm phosphate, but it is measuring the same thing, like feet vs meters. Phosphate counts all of the weight of the P and 4 oxygen atoms, while phosphate-P counts only the phosphorous atom in it, and so read lower.
I discuss it here:
The Units of Measure of Reefkeeping
http://reefkeeping.com/issues/2005-08/rhf/index.php
from it:
ppm-P (part per million phosphorus)
ppm-P is a way to measure total phosphorus atoms in solution. It is equal to the ppm concentration of phosphorus atoms, regardless of what chemical form they take. It is often used to describe the concentrations of phosphorus in dissolved inorganic phosphate, dissolved organic matter (DOM), particulate organic matter (POM), or total organic matter (TOM) in seawater."