Hanna Marine MonitorSimple, User Friendly Tracking of Important Saltwater Aquarium Data A dependable and user friendly tool for monitoring pH, salinity, and temperature in saltwater systems is the Hanna Instruments Marine Monitor. The suction cup mounts that come with the probes allow them to be submerged and are meant for continuous monitoring. The splash proof monitor enclosure can be attached to the outside of your tank using the supplied adhesive fastening strips or