<a href=showthread.php?s=&postid=9786581#post9786581 target=_blank>Originally posted</a> by funman1
Just used the PO3.
Again unimpressed.
The best way to test for PO4 is using an Ion specific colormetric test meter such as the Hanna. I have one very easy to use just add reagent powder to the cuvet and read it it is good down to 0.00 In my tank reading is stable at 0.02 to 0.01