Hach phosphate teststrips are an easy way to check for phosphates (a type of nutrient) in water.

To use them, dip a teststrip into your water sample for a few seconds, then remove it and wait about 1 minute. The strip will change colour based on how much phosphate is in the water.

Compare the colour on the strip to the chart provided on the bottle or packaging. Each colour corresponds to a specific phosphate level: 0, 5, 15, 30, 50 reported in mg/L.