Electricity Problems

[Jaws]

I did exactly that a week ago and I couldn't find the source. I unplugged everything too.

[monocus]

electric eel ?check the heater.it could have a small crack in it

[mattr]

One thing you could do is take a voltage meter and put one end on the grounding probe and one in the aquarium. Then unplug things one at a time to see what is causing the stray voltage. This technique is very similar to just unplugging things one by one and getting a shock.

Try those two but let your tank build up a voltage between checks(unplug everything get a shock then plug the first thing in wait 5 min if no shock unplug it and plug the next device in).