API Phosphate Test Kit

From The Aquarium Wiki
Revision as of 12:40, 15 February 2021 by Arvil (talk | contribs) (Added categories.)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

The API Phosphate Test Kit is used to determine the level of phosphates (PO43-) in your fill water or your aquarium.


The API Phosphate Test Kit is produced by API Fishcare, a subsidiary of Mars, Inc. It is used to test the level of Phosphate in fill water of the water in your aquarium. Phosphate can come from your fill water or decaying uneaten food and dead algae and can contribute to algae blooms. The range of the test is 0 to 10 ppm (mg/l).


Each kit comes with a 5 ml test tube, a bottle of each of two test solutions, comparison color charts cor fresh water and for salt water, and instructions for the user.


  • Rinse the test tube a couple of times in the water to be tested to clear out any impurities and old water.
  • Fill the tube up to the mark (5 ml) with sample water.
  • Holding the bottle of Phosphate Test reagent number 1 over the tube, add 6 drops of reagent.
  • Holding the bottle of Phosphate Test reagent number 2 over the tube, add 6 drops of reagent.
  • Replace the cap and shake. I usually invert the tube over and over for about 30 seconds to mix the solution.
  • Let the tube stand for about 5 minutes to allow thorough chemical reaction to take place.
  • Hold the tube next to the freshwater or saltwater color chart so the white area of the chart is behind the tube and is adjacent to the colors on the chart.
  • The color closest to the tested water indicates the phosphate level in the sample.
  • When the test is complete, discard the sample water and rinse the tube several times. I usually keep about 5 ml fresh water in it with the cap on during storage to prevent mineral buildup in the tube.

See also[edit]

External links[edit]