Phosphate test methods?

Question

Phosphate test methods?

Answer 1

What exactly do you want to test, and how accurate of results are you looking to get?

If you wanted to test soil (your garden or a house plant), there are meters and chemical testing kits.  If you wanted to test water (a stream, lake, aquarium, or your tap water, you could get a different type of meter or test kit to paper strips you dip in the water (less accurate than the others).  

Meters are more expensive and need to be calibrated before you use them.  Test kits are less expensive, but may not have as accurate of results.  For testing water, the paper dipping strips are the least expensive, but also the least accurate.  See these two companies whose products I've used for both water and soil testing - http://www.lamotte.com/

http://www.hach.com/

Answer 2

US EPA method 300.1 - Analysis of Anions using Ion Chromatography.  I'd suggest finding a NELAC certified environmental lab to do it.