2025 Essential Water Monitoring Gear

Stay ahead of the curve with five of the top water monitoring products for 2025. Technological advancements and manufacturing innovations are leading to better quality data, improved price points, and enhanced user experience. And, while the ‘essentials’ list includes several new products, two tried-and-true measurement instruments continue to take a top spot for portable instrumentation.

These five products were developed by industry-leading suppliers, and in addition to extensive manufacturer testing, our science team tested and verified each instrument’s performance at the Fondriest Center for Environmental Studies.

NexSens X3 Data Logger

The X3 is an all-in-one environmental data logger that makes remote data collection possible in a variety of applications. Compatible sensors include water quality instruments, temperature strings, ADCPs, water level sensors, and weather stations. Many popular environmental sensors are automatically recognized and a simple script is all that is needed for other digital sensors.

A marine anodized waterproof housing allows for use in harsh environments on bridges, masts and buoys. An optional pole mount accessory provides a convenient single-point mount to 2-inch pipes and handrails.

4G LTE cellular, Iridium satellite, or dual telemetry options provide cloud connectivity. Data is stored and processed on the WQData LIVE datacenter, and users can access it with any computer browser or by using WQData LIVE Mobile. For environmental monitoring projects on land or water, the NexSens X3 ensures access to data anywhere.

Solinst Levelogger 5

The Solinst Levelogger 5 is a self-contained water level datalogger. The instrument is based on a precision pressure transducer and an accurate temperature sensor. It is housed in a polymer-coated stainless steel body with double o-ring seals. Six pressure ranges are available to support both shallow and deep-water applications.

The Levelogger 5 has a memory capacity of 150,000 temperature and water level data points. Data is transferred through a reliable infra-red optical eye, eliminating the need for direct electrical connection and reducing the risk of electrical surges. The logger can be deployed by a wireline, Kevlar cord or a direct read cable. An internal lithium battery is rated for 10 years of field service.

As with all absolute sensors, the Levelogger 5 will need to be barometrically compensated, so it is often combined with a Barologger 5. Still, the Solinst Levelogger 5’s durable design, high accuracy, and stable performance make it a reliable choice for long-term, continuous water level recording.

Sontek CastAway-CTD

The SonTek CastAway-CTD is a lightweight, easy-to-use instrument for capturing accurate conductivity, temperature, and depth profiles. It is ideal for thermocline and halocline profiling. At 5 Hz sampling rate, the CastAway can free-fall at 1 m/s through the water column. 

With 15 MB of storage, CastAway can store data from more than 750 casts, which includes measurements and site samples. Plots of conductivity, temperature, salinity, and sound speed versus depth are displayed on the color LCD screen. After sampling, raw data can be easily downloaded via Bluetooth to a Windows computer for processing and analysis. 

The SonTek CastAway offers a small and easy-to-use solution for conductivity, temperature, and depth profiling up to 100 meters.

YSI ProDSS Multi-Parameter Water Quality Meter

The YSI ProDSS is a multi-parameter water quality meter that provides extreme flexibility for measuring water temperature, conductivity, salinity, dissolved oxygen, pH, ORP, turbidity, algae and depth. With field-rugged construction, backlit display and keypad, rechargeable battery and cable lengths from 1-100 meters, the system is based on smart sensor technology. Sensors are auto-recognized by the meter and store calibration constants internally, thus facilitating quick changeout.

The meter is waterproof and drop-resistant, with a military-style connector and micro-USB port for transferring data and charging the internal lithium battery. Both GPS and non-GPS units are available, and YSI KOR data management software is included. The company stands behind the product with a 3-year instrument warranty and a 2-year cable and sensor warranty. 

For spot sampling multi-parameter water quality, the YSI ProDSS takes the top spot.

XB-200 Data Buoy

The NexSens XB-200 Data Buoy is ideal for water monitoring applications requiring portability and quick deployment, yet strong enough for rough water. The hull and solar tower on the XB-200 are made from UV stabilized polyethylene and filled with a lightweight, closed-cell foam, which keeps the buoy afloat even if pierced or damaged.

Batteries are housed in a waterproof compartment in the buoy hull with additional room for measurement electronics and telemetric equipment. Three integrated 15-watt solar panels provide 45-watts of solar charging.

Three 4″ diameter pass-through ports allow for water sensor deployment with connectivity to data logger. A top plate supports a solar marine light, weather stations, and other sensors.

Striking the perfect balance between size, durability, and versatility, the XB-200 is in a class of its own.