A note on pH
I've done a lot of reading on Reef Central and elsewhere concerning pH measurement. I guess we have no guarantee of getting accurate pH measurement unless we buy a true scientific instrument, which is quite expensife. I have two Pinpoint pH monitors that give different readings of the same water, despite just being calibrated and having new sensors.
Different brands of salt mixes are manufactured to come out with different pHs. I used Kent at one time, found the pH very low and variable. I've switched to Tropic Marin and found the pH comes out about right.
Calibration fluid for meters has to be new is also not always accurate.
Generally, the consensus is that pH meters are more accurate than test strips.
One good thing - if you aim for a pH of 8.2, you have some latitude - the pH can be a bit higher or lower and still be acceptable.
Thales is right - watch your livestock carefully - if its doing well, your pH is OK.