quarantine tank ???

[Myka]

Unless there is always a new fish coming and going in the QT, the biological bacteria will die with no food (no fish), so there is no point in keeping it running.

I have always just set up a QT as needed. I have a small sheet of filter media in my sump (that I change weekly), and handy enough if I trim 1/2" off the end it fits right into the AquaClear I use on the QT, so it is always in the sump and available to "seed" the QT. I also fill the QT with at least 50% water from one of my other tanks, but preferrably 100% "used" water. The QT is always setup, just no water in it. I can't justify keeping it running with water when fish rarely pass through it, it would just be a pain in the butt to keep the bacteria colonies from dying and a waste of electricity.