Stray Voltage

[scherzo]

Hi all,

I had thought my skimmer was creating some stray voltage but it was an MJ -1200 that I used in my sump.

The Maxi-Jet showed 32V when it was plugged in.

However - With everything else it shows about 3.4 - 4.0 volts.
Is this acceptable? Should it be closer to zero? What do your tanks read?

I've googled this to death and answers seem to be all over the place. Just want to see what things are like locally.