HM Digital Replacement pH Sensor for HM-500 and HM-200 Meters

Restore Accurate pH Readings on Your Meter - Single Replacement Sensor

A worn pH sensor makes readings drift and forces you to doubt every nutrient adjustment. This replacement sensor lets you swap the probe instead of buying a new meter. It fits the HM Digital Hydromaster 500 continuous meter and the Hydromaster Portable HM-200.

Sold as a single sensor, it suits growers who need one spare for a meter already in use, whether in a home hydroponic system or a commercial room running several meters.

Key Features & Benefits

• Dual-model fit — works with the HM-500 and HM-200, so one part number covers both meters.
• Measures pH — returns the nutrient solution reading you rely on for vegetative growth and flowering.
• Replaces only the probe — keeps the rest of your meter in service.
• Storage cap — protects the sensor tip between uses.

Who Should Use HM Digital Replacement pH Sensor

Use it if your HM-500 or HM-200 gives inconsistent pH readings or no longer holds calibration. It suits home gardeners and licensed commercial growers who monitor hydroponic reservoirs.

About HM Digital Replacement pH Sensor

HM Digital makes the Hydromaster meters this sensor replaces. It is a pH-only replacement part sold each, for the HM-500 continuous meter and the HM-200 portable meter.

Frequently Asked Questions

Q: Which meters does this sensor fit?
A: It fits the HM Digital Hydromaster 500 and the Hydromaster Portable HM-200. Check your meter model before ordering.

Q: When should I replace my pH sensor?
A: Replace it when accuracy starts to degrade or readings become inconsistent, even after calibration.

Q: Do I need to calibrate a new sensor?
A: Yes. Calibrate with pH buffer solutions before relying on readings, as you would with any pH probe.

Q: Does it measure TDS, EC or temperature?
A: No. This part measures pH only. Your meter handles its other functions separately.

Q: How should I store the sensor?
A: Keep it in its storage cap with the sponge when not in use. This protects the tip from damage.