I bought a Marineland Visi-Therm Stealth 250 watt heater which I plugged in last night for the first time. My question is that all my heaters in the past have had a red light come on to signify the heater is heating and also working. I see nothing on this heater to tell me it is doing anything and the only way I know is to check the thermometer. Is this the case with this heater? Also is this a good reliable heater?