I have a 200 Watt Aqueon heater. Have not noticed any kind of temp readings on the temperature gauge, the sticker type, and yes I know, Iwill be replacing the sticker themo with an actual thermometer. But there is no color on the temp gauge, all black. I have my heater on, and submersed, yet the red light dont come on either. Is there anyway I can check to see if the heater is operational?