HI98319 Hanna Marine — Waterproof Salinity Tester IP67 0-40 ppt Reef - Hanna

Hanna HI98319 waterproof salinity tester for reef marine aquariums

The Hanna HI98319 Marine Salinity Tester is a pocket-size IP67 waterproof salinity tester built for reef keepers and marine aquariums. Unlike an optical refractometer that needs calibration and visual interpretation, the HI98319 displays salinity in ppt, PSU or SG with automatic temperature compensation — dip the probe, press a button, read the result. Single-point calibration at 35.00 ppt with Hanna HI70024P solution.

What this tester brings to a reef keeper

• Three measurement units: ppt (g/L), PSU and specific gravity (SG) — switch to whichever you prefer.
• Automatic temperature compensation from 5 to 50 °C — cold samples no longer skew the reading.
• IP67 waterproof rating — survives an accidental drop into the sump or display.
• Automatic single-point calibration at 35.00 ppt (Hanna HI70024P solution sold separately).
• Large LCD display, low-battery indicator, stability indicator on-screen.
• Stainless probe with integrated temperature sensor — no separate temperature calibration.

Technical specifications

• Model: HI98319
• Salinity: 0.0 to 40.0 ppt (extended to 70 ppt), resolution 0.1 ppt
• PSU: 0.0 to 40.0 PSU, resolution 0.1 PSU
• Specific gravity: 1.000 to 1.041, resolution 0.001
• Salinity accuracy: ±1 ppt, ±0.001 SG at 25 °C
• Temperature: 0.0 to 50.0 °C, resolution 0.1 °C, accuracy ±0.5 °C
• Temperature compensation: automatic 5 to 50 °C
• Calibration: automatic single-point at 35.00 ppt
• Waterproof rating: IP67
• Power: 3 V CR2032 lithium battery (installed)
• Warranty: 2-year Hanna Instruments

How to use

• Calibrate once a month with Hanna HI70024P 35.00 ppt solution.
• Dip the probe 2-3 cm below the water surface.
• Wait for the stability indicator on the display.
• Read directly in ppt, PSU or SG depending on the setting.
• Rinse the probe with RO water after every measurement and dry.

Why get this tester from ReefSolution

For full reef salinity control we also recommend:

• Hanna HI70024P — 35 ppt calibration solution — the dedicated standard for the HI98319 monthly single-point calibration.
• Hanna Checker HC HI772 dKH alkalinity — KH monitoring, run alongside salinity checks.
• Hanna Checker HC HI758 marine calcium — completes the Ca/KH/Mg trinity.
• Hanna Checker HC HI783 marine magnesium — magnesium every 2-4 weeks.

Frequently asked questions

How accurate is the HI98319 versus an optical refractometer?

Accuracy ±1 ppt (±0.001 SG) with automatic temperature compensation — on par with a well-calibrated refractometer, without the visual interpretation or manual temperature adjustment.

How often should the HI98319 be calibrated?

Once a month with the Hanna HI70024P 35.00 ppt solution — more often if the tester is used heavily or stored in variable conditions.

Does the HI98319 work in freshwater or only saltwater?

It is tuned for marine water (0-40 ppt). Freshwater readings are possible but fall outside the calibrated range — a TDS meter is more appropriate for freshwater.