Apera Instruments 5051 Compact Salinity Pen Tester

The Apera 5051 is a pocket-size salinity pen tester built for fast, reliable salinity checks in the field, lab, or at home. Part of the Eco Series, it features a dedicated fixed salinity sensor optimized for rapid stabilization and accurate readings — no complex setup, no multi-parameter confusion. Slim enough to slip into a shirt pocket, the 5051 is the go-to tool for routine salinity monitoring across pools, aquariums, irrigation, and general water quality applications.

Why Choose the Apera 5051?

• Dedicated Salinity Sensor — fixed, parameter-specific probe delivers fast stabilization and accurate readings without cross-parameter interference
• Ultra-Compact & Lightweight — approx. 0.5 lbs; fits in any pocket or field kit for true on-the-go testing
• Simple Point-and-Read Operation — no complex menus; instant salinity verification for everyday users and field technicians
• Cost-Effective — professional-grade accuracy at an economical price point; no lab instrument required
• Easy Maintenance — rinse and store at room temperature (15–25°C); minimal upkeep required

Ideal Applications

• Swimming pools and spas: salinity monitoring for salt-chlorine generators
• Freshwater and saltwater aquariums: routine salinity checks
• Irrigation and agriculture: soil water salinity screening
• Environmental field monitoring: general water quality verification
• Food and beverage: basic brine and salinity checks

Eco Series Model Comparison

Technical Specifications