MiniMon provides unattended, around the clock monitoring for fish marked with an ISO PIT Tag. MiniMon can simultaneously collect data from several ISO transceivers. The collected data is transformed into interrogation files which are partitioned by a specified time interval. These interrogation files are uploaded from the field site to the central PTAGIS database and available to researchers in near real-time. MiniMon provides visual diagnostic information about the current interrogation process in addition to robust logging features.