Just remember garlic does not cure ich it only helps build your fish's immune system to help fight it off. With that said yes the Powder could have introduced it into the system which is why you should have a quarantine tank setup for new fish. Stray voltage you can "try" putting one of the leads of a meter into the water and the other on a ground source (like a copper water pipe) and if you have a lot of voltage than yes its bad. You will never get rid of stray voltage in a tank, however, without a grounding probe. But with a grounding probe you should only use it when your in the tank cause otherwise you may never know there was truly a problem.


