Red Sea's colorimetric Phosphate test kit provides a quick and reliable measurement of Phosphate in your aquarium to an accuracy of 0.1ppm PO4.
This test kit, in conjunction with Red Sea's Nitrite/Nitrate test kit, enables dosing of NO3: PO4- X (Biological Nitrate and Phosphate reducer)

Red Sea Phosphate Test Kit Includes 100 tests.

Manual
MSDS