View Full Version : How do YOU test for calcium?
I've read that calcium test kits have a hard time of measuring levels as high as what we're testing for. One recommendation was to mix 1/2 tank water with 1/2 RO/DI water and then double the test result. The idea is that the test kit can read a result of 200 easier than it can a result of 400, for example.
Any opinions on this? Anyone else testing for Ca this way?
Satchmo
01-23-2003, 2:19 PM
That's interesting, hadn't heard that before. Calcium test kits have a rocky rep anyway. I use Salifert, which seems to be the gold standard. I did toy with diluting sample water in an attempt to make reagents last longer, but with the unmarked shelf life of most of these things, I figured that wasn't the brightest idea I've had. I'd be interested in seeing other info about this if you turn up anything.
I use Salifert too. I'm wondering if this diluting practice is only necessary for the 'lesser' test kits.
I just ran a test the regular way and another with 50% RO/DI. The regular test gave me a result of 400 and the 50/50 test gave me a result of 390.
The guy who developed the Salifert tests posts over on Reef Central. I'll see if I can PM him and ask him what he thinks. If I hear back from him, I'll let y'all know what he has to say. Hmm, I wonder about the alk and Mg tests too.