I know its not good to have voltage running through your water, but I seem to have at least a little bit in all of my tanks. I have pretty good equipment and Im thinking this has to be normal. Ive noticed alot of the voltage is comming from my heaters. One of them a visitherm stealth heater, and the another is a hydor theo. My fish have been living with the voltage for quite some time, and behave normally. I dont see how this would effect the fish considering they are not grounded. So, whats up ? Do you have voltage in your tanks ?