Quote Originally Posted by jjb View Post
will try extra ground probe in the sump. i have tried the profilux sat on the floor in front of tank , sensors then go straight to the tank, not next to any power cables and i still get the strange readings its as if the tunze backfeed the profilux. will post after i have done the extra probe.
i had the same but after changing to a new GHL redox probe and replacing a new ozon gernerator my mV is back to normal. If you have done all this and still the same idd replace your tunze!