As the weather warms up, I'm determined NOT to start the season with a green pool as was the norm. I didn't get too lax over the winter and so the sudden increase in chlorine usage is not going to catch me by surprise thanks to everyone here.
My question today is if reagents can go bad? I grabbed my DPD test and got a zero reading for FC. It freaked me out so I pulled out my K2006 (FAS-DPD) and found a reading of 3ppm (pH matched between the two tests). The 'basic' kit is at least a year, if not two, old.
If so, I have to decide if I want to just use my full test a few times a week or replace this kit so I only use the K2006 on the weekends (like I did the second half of last summer once things were in stasis). Your opinions on this would be nice too.