PH test really Orange

I just did a quick test: Got a pool water sample and added Phenol Red. Added acid demand test reagent until I had the pH slightly below 7.4, giving a light orange. Then I added more Phenol Red until the colour looked similar to the dark orange from your picture:

View attachment 318570

Based on that I would say that the Phenol Red concentration in your reagent bottle probably increased over time (due to evaporation? - Maybe the bottle got left open for too long at some point? Or that's just what happens when the stuff gets older?). Or the drops got larger for some reason. Time to get new reagents. In the meantime you could try if a test with a larger water sample or with less Phenol Red gives more reasonable results.
Ok. Thanks ! I have a whole bunch coming from Amazon over next 2 days - reds, greens, 16oz OTO , 16oz CYA , so will try again. My 0004, ironically, is the only one IN date lol.
 
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