The temperature probes for the reefkeepers are getting difficult to find so I'm interested in finding a working replacement. n2585722 has done some investigation with a 10k NTC thermistor and I have tried one but find it to be too sensitive for use. The digital aquatics probe gives a nice square wave on the graph while the thermistor is very unsteady. Maybe this is the wrong thermistor or maybe there is some stabilizing circuitry built into the DA probe? My electronics knowledge is limited so I'm hoping someone can figure out how to do this before our probes quit working.