Thank you for the information. Good to know. It just sucks to be colorblind and maintaining a pool when most systems rely on color readings. I'm hoping this testing system keeps me closer to real numbers, not relying for someone else to see/guess colors for me. Or the last choice to rely on my supplier to tell me "looks good, don't need to buy anything today".When was the last time the system was calibrated against a known standard? Do you change the cuvettes every season with new ones? Digital testers are fine but TFP has seen problems with them giving all sorts of false readings and it’s usually because they are out of calibration.
Also, some of the biguanide reagents are known to be positively interfered with by algaecides. So if you are regularly using algaecides on top of the baquacil sanitizer, your testing could be showing a false-positive interference (higher reported level than actual). You would need to call up LaMotte and speak to someone in their technical division (ie, not customer support) to know if the reagent they use is susceptible to interference from ADBAC type algaecides (linear quaternary amine algaecides).
It is beginning to clear up some, planning to watch it closely, give it another kick today.