API freshwater master test kit question

[Nofrnds2pla]

I hope I’m putting this in the right place. My question is on the pH test. The regular pH goes from 6.0 to 7.6. The high range pH goes from 7.4 to 8.8.. why would not the 7.4 be in the first pH test chart instead of the high pH chart? The last two readings on the first test are 7.2 and 7.6 and the first two in the high pH are 7.4 and 7.8. The 7.4 appears to be in the wrong place to me! Any input would be helpful. Thank you.

 

[Essjay]

It just so the two overlap slightly.

 

[Nofrnds2pla]

I hope I’m putting this in the right place. My question is on the pH test. The regular pH goes from 6.0 to 7.6. The high range pH goes from 7.4 to 8.8.. why would not the 7.4 be in the first pH test chart instead of the high pH chart? The last two readings on the first test are 7.2 and 7.6 and the first two in the high pH are 7.4 and 7.8. The 7.4 appears to be in the wrong place to me! Any input would be helpful. Thank you.

To add to my question….when I use ph test#1 my ph is 7.6 when I use ph test #2 my ph is 7.4? I am confused…..thanks

 

[Nofrnds2pla]

It just so the two overlap slightly.

Hi Essjay
See my added note below. So what is my pH 7.6 from test number one or 7.4 from test number two?

 

[Essjay]

That's the same as mine. I call that 7.5.

We don't need to know pH to pinpoint accuracy. We need to know if -
the pH is within the range needed by the fish we want to keep (though it can be slightly outside that range if GH is well within the species' range) and
that pH is remaining stable. To check pH in a planted tank it should be measured at the same time of day because pH does vary over 24 hours. This is because plants take up CO2 when it's light and make CO2 when it's dark. This small pH change which won't harm fish.