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aka_BigRed · 04/08/2005, 02:04 PM

I have a question about ion-selective probes (calcium from your recent article in Reefkeeping) and their raw output.

I'm working on a project to develop a DIY reef controller and I'd thought about adding a Ca probe to monitor Ca levels. From your article, the electrode puts out a variable milivolt reading based on the concentration of Ca, but do you know where I could find out the conversion factor from mV to PPM concentration? Is it a direct relationship or log scale or some strange equation? I'm having a tough time finding out the conversion factor/equation that the meters use. I also had the same question for a Nitrate probe.

Adding ORP should be easy since the readings and standard units people use are just plain milivolts. I just can't get info on the output conversion scale for other "fun" probes.

Thanks!

04/08/2005, 02:04 PM	#6
aka_BigRed Registered Member Join Date: Mar 2004 Location: St. Paul, MN Posts: 162	I have a question about ion-selective probes (calcium from your recent article in Reefkeeping) and their raw output. I'm working on a project to develop a DIY reef controller and I'd thought about adding a Ca probe to monitor Ca levels. From your article, the electrode puts out a variable milivolt reading based on the concentration of Ca, but do you know where I could find out the conversion factor from mV to PPM concentration? Is it a direct relationship or log scale or some strange equation? I'm having a tough time finding out the conversion factor/equation that the meters use. I also had the same question for a Nitrate probe. Adding ORP should be easy since the readings and standard units people use are just plain milivolts. I just can't get info on the output conversion scale for other "fun" probes. Thanks!