The fogger is not necessary, you can hand mist once or twice a day depending upon what the humidity levels are. Lowes or homedepot sell small pressurized hand misters in the gardening section for around 7 dollars.
Even one of the small hand misters for plants that you can buy at the Dollar Store for a dollar would be easy enough for a single tank. You want to keep the humidity at around 80%+. If you have condensation on the glass and it's damp but not standing water, you should be okay.