Robo-Tank Isolated PH Circuit

[Rob F]

That has gotten worse, out of acceptable limit now, but the main problem is it's takes a long time to get a reading, I think I caused the issue by putting the probe in my tank too often without isolation. Based on Atlas if the water being measured has stray voltage it can damage the probe so isolation is required to prevent that. Mysteriously my tank has a high level of current flowing through it as the meters go off the charts when I simply touch the water with the probe. After doing this the responsiveness of the probe is horrible, if I move from buffer 4 to 7 it can take an hour to finally get a reading it will stick to, it slowly creeps up 6.432, 6.433, 6.434, etc... until it hits the max. Now I want to do a final 3 point test but having a hard time. When I started with the cheap probe I did do a 4 and 7 calibration that worked perfectly so I'm sure it'll be ok.

I ordered the probe on Amazon last Friday with 2 day shipping and to my surprise it still hasn't shipped, they've never been this slow as this is a Prime item. I hope they ship it tomorrow.