Which measure of CH and TA?

[tfoggo]

My photometer gives me the option of two readings when I test for CH or TA:

CH: produces readings in CaCO3 and Ca
TA: produces readings in CaCO3 and HCO3

Having read around TFP a bit, I think I should be paying attention to the Ca reading for CH and the HCO3 reading for TA - am I right?!

 

[JVTrain]

You actually want to use the readings for CaCO3 for both TA and CH. CaCO3 is used as the equivalent for pool testing by convention.

Is there a reason you're using a photometer versus Taylor reagents for testing?

 

[tfoggo]

You actually want to use the readings for CaCO3 for both TA and CH. CaCO3 is used as the equivalent for pool testing by convention.

Is there a reason you're using a photometer versus Taylor reagents for testing?

Thanks JVTrain.

I chose this photometer when I took on my first pool 4 years ago because I figured that it would provide more accurate and consistent readings than a manual kit. Also, it offers the capability to test all the elements of water balance I need with one device whereas other options seem to require buying different kits for different elements. Did I choose wrong?! Are there downsides to photometers? I don't think Taylor test kits are available in the UK, but I'm sure there will be equivalents available.

All the best.

 

[JVTrain]

Photometers can work just fine, as long as they are frequently calibrated and verified for calibration. There is no substitute for reliability and accuracy for the FAS-DPD test for FC/CC. I strongly recommended having that test for maintaining your chlorine levels.

 

[tfoggo]

Thanks again JVTrain.

I confess that I've only had my photometer calibrated once since I got it, so will do that more frequently. Also, I've just ordered a set of test solutions for it that will apparently tell me whether or not it needs calibration.

Thanks for the advice!