BIG TROUBLE!! Need advice please.

[Myka]

I would believe Elos over Hanna, especially when it comes to calcium. There have been reports of inaccurate numbers with the Hanna calcium kit and people have been using the Elos for a long time with reliable results. 100-150 ppm calcium is hard to believe though...

Here's an idea...we know that bucket of IO salt will have calcium around 380 ppm at 1.025, so mix up some saltwater for 24 hours and test that with both Hanna and Elos. Since there is a 200 ppm difference between the kits you will be able to tell which one is out to lunch.

Don't forget to roll that bucket of salt before using it too!!