Gobius Pro Tank Level Gauge with 1 Sensor

External Tank Monitoring Without the Drilling

Traditional tank level sensors require you to cut into your tank, thread fittings, and risk leaks from day one. The Gobius Pro takes a completely different approach: the sensor attaches to the outside of the tank wall using 3M adhesive tape, with no penetrations, no fittings, and no contact with the fluid inside. This makes it suitable for tanks that are difficult to access or where drilling would compromise the tank's integrity.

Installation is straightforward. Clean the tank wall with the included 3M cleaning tissue, peel the backing from the sensor tape, press the sensor firmly onto a vertical section of the tank wall, and connect the two-metre cable to your 12-24V DC power supply. The sensor must be placed at least 35 mm from any edge or adjacent sensor, and the tank wall temperature must be above +20°C during installation to ensure proper tape adhesion.

How the Sensor Technology Works

The Gobius Pro uses a vibration-based sensing method to determine whether fluid is present at the sensor's position on the tank wall. The sensor exerts a small mechanical force onto the tank wall, causing it to vibrate. An internal accelerometer measures those vibrations and transmits the data to the sensor's onboard processor. The processor's algorithm then calculates a vibration value and determines whether the fluid level is above or below the sensor.

The difference in vibration behaviour between a tank wall in contact with fluid and one exposed to air is what allows the sensor to make its determination. This approach works across a wide range of tank materials, including stainless steel, mild steel, aluminium, polyethylene, and fibreglass, provided the wall thickness does not exceed the specified limits for each material.

Bluetooth Monitoring on Your Smartphone

Each Gobius Pro sensor includes built-in Bluetooth Low Energy (BLE) communication, compatible with Bluetooth 4.2 and later. The free Gobius app, available from Google Play and the App Store, connects automatically to the sensor without requiring manual pairing or a PIN code. From the app, you can name your tank, select the fluid type, set the measurement interval, configure alarms, and perform calibration.

The app supports a range of fluid types including freshwater, gasoline, diesel, grey water, waste or black water, and oil. Measurement intervals can be set anywhere from 10 seconds to 48 hours, or disabled entirely, depending on how frequently you need updates. Once configured and calibrated, the sensor operates independently and does not require your phone to be present.

Alarms, Outputs, and System Integration

Beyond smartphone monitoring, each Gobius Pro sensor includes two independent digital outputs that provide on/off signals. These outputs can be configured to trigger when the fluid level is above or below the sensor, or set to always on or always off. You can connect the outputs to indicator lights, relays, or buzzers to create standalone visual or audible alerts without relying on a phone.

The included panel features one red and one green LED, giving you a simple at-a-glance status display at the helm or near the tank. The digital outputs also allow integration with bus systems or pump controls, so you can automatically start or stop a pump based on tank level.

• Configure digital output 1 to illuminate the red LED when the level is above the sensor, indicating a full or overfill condition.
• Configure digital output 2 to illuminate the green LED whenever power is supplied to the sensor, confirming the system is active.
• Use the outputs to trigger a relay that starts or stops a pump at a defined high or low level.
• Connect to buzzers or external alarm systems for audible overfill or low-level warnings.

Scalable: Use Up to Nine Sensors on One Tank

A single sensor can only tell you whether the fluid level is above or below that one point on the tank wall. By adding more sensors at different heights, you build a more complete picture of your tank's contents. The Gobius Pro system supports up to nine sensors on a single tank, and the Gobius app can manage multiple tanks simultaneously.

When two or fewer sensors are installed, the app displays a dot in red or green to indicate whether the level is above or below each sensor. With three or more sensors, the app switches to a bar chart view that gives a proportional representation of the tank level. Sensors should always be installed starting from the lowest position and working upward, one at a time.

Compatible Tank Materials and Wall Thickness Limits

The Gobius Pro sensor is compatible with the most common marine tank materials. The maximum wall thickness for reliable operation varies by material, so it is important to measure your tank wall before purchasing.

• Stainless steel: maximum 3 mm wall thickness
• Mild steel: maximum 3 mm wall thickness
• Aluminium: maximum 5 mm wall thickness
• Polyethylene: maximum 12 mm wall thickness
• Fibreglass: maximum 8 mm wall thickness

What's Included in the Box

The Gobius Pro Tank Level Gauge with 1 Sensor includes everything needed for a basic single-point installation.

• 1 Gobius Pro sensor with 2-metre cable
• 1 cleaning tissue (3M) for surface preparation
• 1 extra sensor tape (3M) for remounting if needed
• 1 panel with red and green LED indicator lamps
• Quick guide for installation reference

Specifications

• Supply Voltage: 12-24V DC
• Bluetooth Version: BLE (Bluetooth Low Energy), from version 4.2
• Smartphone Compatibility: iOS (iPhone) and Android
• Digital Outputs: 2 x digital on/off signal outputs
• Maximum Sensors per Tank: 9
• Sensor Cable Length: 2 metres
• Compatible Tank Material - Stainless Steel: Maximum wall thickness 3 mm
• Compatible Tank Material - Steel: Maximum wall thickness 3 mm
• Compatible Tank Material - Aluminium: Maximum wall thickness 5 mm
• Compatible Tank Material - Polyethylene: Maximum wall thickness 12 mm
• Compatible Tank Material - Fibreglass: Maximum wall thickness 8 mm
• Minimum Distance from Tank Edge or Adjacent Sensor: 35 mm
• Installation Temperature (Minimum): +20°C (+68°F)
• Operating Temperature Range: -10°C to +60°C
• Mounting Method: 3M adhesive tape, external tank wall surface
• Measurement Interval Options: 10 sec, 30 sec, 1 min, 2 min, 1 hour, 4 hours, 24 hours, 48 hours, or never
• Supported Fluid Types: Water, gasoline, diesel, grey water, waste/black water, oil, other
• Mounting Orientation: Vertical tank wall only
• Patent: US 8,448,509; Sweden 0701520-9; EU 2165164

Key Features 

• External mounting with no drilling required: attaches to the outside of the tank wall, eliminating the risk of leaks from tank penetrations
• Works with virtually all onboard tank types: suitable for freshwater, fuel, diesel, grey water, black water, and oil tanks
• Bluetooth smartphone monitoring: check tank status from your iPhone or Android device using the free Gobius app
• Fully configurable from your phone: set tank name, fluid type, alarm behaviour, measurement interval, and digital output behaviour through the app
• Two independent digital outputs: trigger indicator lights, relays, buzzers, or pump controls directly from the sensor without needing a phone
• Included LED panel provides at-a-glance status: red and green indicator lights give a clear visual reading near the tank or at the helm
• Expandable to nine sensors per tank: add sensors at multiple heights for a more detailed view of tank contents
• Supports overfill and low-level alarms: position sensors to warn you before a tank overflows or runs dry
• Pump automation capability: configure outputs to automatically start or stop a pump based on high or low fluid levels
• Wide material compatibility: works on stainless steel, mild steel, aluminium, polyethylene, and fibreglass tanks within specified wall thickness limits
• Operates independently after setup: once calibrated, the sensor functions without a phone connection, using the included LED panel for status