When allowing a brand new set up aquarium with live sand (not rinsed) to settle, should the filter be running? I left the aquarium to settle for 12 hours, filter off, heater running. I understand the tank can remain cloudy for 24-48 hrs. Should I turn on the filter now? Additionally, the heater turns off when the water around it is warm, but isn't warming the entire tank. I assumed turning on the filter would move the water enough around the heater to warm the entirety of the tank. I do have a separate sinking thermometer in the tank to see if that will catch a change in temperature. Otherwise, I'm unsure of the issue. Faulty equipment?