Decided to try an inkbird itc-308 managed to calibrate and set it up .I have set my desired temp to 27.5c I have connectem my 300w fluval heater to it have removed the guard.Now when the water temp drops to about 27.2c I hear the inkbird click and the heating led on the inkbird lights up but the heater display is off I unplugged the fluval heater and plugged it back in and the little display lights up when desired temp is reached the inkbird switches off the heater .It seems that when the inkbird then needs to switch on the heater the heater is not coming on anyone else have this issue I want to buy 2 more but want to see how good they work first.