Need help with Taylor Calcium test kit

[JimK]

(Sorry for the long post. If you want to skip the background info and get to the heart of my question, skip to the bolded section.)

Years ago I purchased a Taylor calcium test kit. According to the instructions at that time, I was to add drops until the sample turned from purple to blue. I was unable to tell when that change occurred, so I gave up on it an just relied on pool store testing for calcium.

Fast forward to now. Recently Ben asked me what my calcium level was and I gave him the figure from my last pool store test for "Total Hardness". Looking at my records for the past many seasons, TH seems to always seems to be in the 200-260 range (most often 240ish to 250ish). BTW, the nearby pool store uses a computer (Alex?) to test; sometimes it gives wacky results so I don't really trust it. The closest store that uses the Taylor kits is over a hour away.

Out of curiosity, I looked on the Taylor site to see if there was another test kit available. In the current instructions, it indicated the sample will change from red to blue. I figured this must be a change from the old kit and thought I could probably see the change from red to blue.

Today I bought the appropriate reagents and followed the instructions carefully. The sample initially did not turn red as indicated in the instructions; best I can tell it turned kind of very pale pink/purple. Adding the reagent R-0012 dropwise I could not tell when the change to blue occurred, partly because the color was so pale, and partly because I have trouble telling when purple becomes blue. I tried twice, carefully following the instructions, but no luck. It seems this is pretty much the same kit that I had tried years ago.

Is there anything I can do to make this test easier to read? If not, is there another reliable kit I could use?

Interestingly, I have no trouble with the Taylor TA test (green to red) or matching the colors on the Ph test. In my first season (2004) I did have a chlorine kit that had different shades of yellow that I had trouble matching, so I switched to the DPD powder kit (pink to clear; love this kit!).

Thanks. I appreciate any help/feedback.

*edited to correct color change for TA