API Calcium Test Kit Saltwater Aquarium Water 1-Count Kit, 69L (69L)

Cost is high

People debate the accuracy of this all the time when compared to the higher end test kits. For me, it simply works. The resolution of the testing is to 10 ppm and other products go .5 ppm. I'm personally okay with knowing I'm either 420 PPM or 410 PPM weekly. The point is to graph and understand the trend line over time. If you're trying to track specific daily fluctuation you're better off going with a higher end kid. For me it works and is simple to use for my application. Tip: 10 drops of Bottle #1 and shake. When you start bottle #2 you'll start seeing a trend based on your tank consumption. For my tank, I'm consistently at 400+ PPM. So for Bottle #2, I put in 19 drops at the same time and shake. Then add additional drops until I see the color change. Don't add a drop and shake starting at the beginning or you'll be there all day.

All of the API test kits are easy to use and reasonably accurate. I use several of their assays to monitor water quality in a commercial aquaponics farm. They are fast and as reliable as could be expected. The only concern with colorimetric assays like these is the subjectivity of the result, often the distinction between colors on the reference scale are slight and may be interpreted differently by different users. This calcium test, however, is one of the least subjective as the color changes very clearly from pink to blue. When I have sent water to university labs for comprehensive testing, the API calcium test result was always within 10ppm of the university result. Can't ask for much more than that for $7.

J'utilisai le test TETRA qui est une vrai galère avec 2 produits et une poudre et surtout qui ne donne pas les bons résultats... J'avais remarqué ce test utilisé dans une animalerie mais non commercialisé par cette dernière... Enfin le produit simple et fiable que j'attendais! je vous le recommande vivement

It woks great easy to use