This morning at about 2am one of my inkbird temp controller alarm went off went down to investigate the inkbird was showing a temp of 32.c but the heater was off got my thermometer it showed the tank water as being 23.8c did a quck swap round of the probes showed the same temp as thermometer so the probe has failed after 4 months this the stainless steel probe . I have decided to get the 306t which is the aquarium version my 2 other inkbird's have the metal probes as well the only thin the 306t dose not have the alarm