Relay to power AC Item

Hello all, I am starting down a project and need some advice as to what sort of relay I need. To explain, I have gecko in a low humidity area, to compensate for this I have a very crude device called a repti-fogger to provide additional humidity. It is so crude I cant control it, its either 100% humidity or 30% so I need to put some additioinal control on it. I want to use one of my arduino;s sitting around to help control the humidity.

I am buying a temperature/humidity sensor and want to turn on/off the device based on the humidity I need to keep inside the tank.

What sort of relay do I need?

Im not sure how much current the fogger is drawing, but my initial thoughts are to control this through the arduino 5V power to trigger the AC power line to on/off.

Any suggestions are greatly appreciated!

The easiest way is a relay shield or SSR. Your humidifier would only be low current so either will work.

Just make sure you take all precautions with the mains voltage. Remember that the relay shield will have high voltage on the trace side of the board.

A SSR would be safest as you can separate the mains voltage in a box and just feed the input from the Arduino via a resistor.