Following because I have the same problem with the salifert test. I end up getting almost the same results as the op and have since given up using it. I normally use a Hannah kit to test my calcium and avg. anywhere from 400-425. I figured I'd give the new salifert one a try and cannot get the same results as the hannah, and cant even get the test to return legible results compared to the hannah. I use salifert for everything else but phoshate so I am familiar with their processes and prefer the ease of them but just cant get this one to work for me.