Is the ST100J-XX probe compatible with the UTRED 30-16 Temp. Data Recorder? Also, can the probe be used in a salt water solution? Thank you.

Yes, the ST100J-XX probe can be used with the UTRED30-16 data logger.  The probe can be used in salt water however, great care must be taken so that only the stainless steel portion of the probe is submerged.  If the junction of the stainless steel and cable becomes submerged it will cause corrosion in the sensor and cause it to fail prematurely.