I've been consistently testing between 8.0 and 8.2 with my Red Sea pH test in my 2g jarquariums. I also acquired a HM digital pH pen, which was way out of whack -- it consistently gave readings of 9.0-9.1, which I thought to be highly improbable, so I acquired some pH calibration solution off of Amazon (yes, yes, but I don't have a LFS). I recalibrated the pen with the 7.0 solution and then tested it with the 4.0 solution -- readings appeared to be spot on. Actual readings on the jarquariums, though, resulted in pen readings of 7.8-8.0. The Red Sea test, though, is showing between 8.2 and 8.4. (it was off the charts before I added aeration and removed some macro).The Red Sea test hasn't expired. SG is at 1.025 in both at 26C. Am I stuck in a guessing game? Do I simply bite the bullet and go for a conductivity test? Nothing really rides on this right now, but I like to keep my macro and lone mushroom frag happy...and I am starting up a Fluval Evo. Thoughts?