Weird Sensor problem

[Mistahbrock]

Hello folks

A couple of days ago I my PH sensor started to act weird.

From stable readings over the past couple of years ( with a yearly probe replacement ) the reading went from normal reading to sky high.

Of course I changed to another probe, calibrated and expected the reading tone be normal.

They were still high and I started to disconnect other stuff as the readings from my aquarium water I a cup was normal but reading from the exact same water in the tank was sky high.

After I disconnected heaters and sterilizer, the only power source left was the PSU for the mitras lightbar

So after I unplugged this one the reading went from sky high to normal again.

The LB PSU and the GHL Profilux 4 is connected to the same wall plug with the same ground reference so I just don't get it.

Does anyone in here have similar experiences ?

Does any GHL staffers know why I have this weird issue ?

I had the impression that the probes was galvanically isolated so this is indeed unexpected.

For now I will shutoff the PH probe.

Best regards, Brock