The Water Guardian R500 is a small water quality and dynamics monitoring device, with a float diameter of 0,50 meters and a full year of work without maintenance this is a simple device for all types of jobs. Readings can be taken either dependent or independently and the probe will function correctly in fresh, salt or brackish water.

The WG R500 is fully built in composite, withstanding impacts, solar exposure, salt water and corrosion without a problem. Each section is laminated using UV-stabilized, isophthalic polyester resin reinforced with Kevlar* and glass fibers in order to obtain maximum durability, crash resistance and water impermeability. With thicknesses ranging from 3 up to 7mm this structure is rigid durable and reliable.

The small WG R500 packs a punch and can be upgraded with up to 32 sensors, and 4 or 5 solar panels for larger energy independence.

Simplified modular structure and electronics allows for easy upgradability and maintenance. Devices can be installed to meet specific client needs from low cost energy efficient sensors to high precision instruments.

The WG R500 can generate alerts and send them to mobile devices via Wi-Fi or Bluetooth. Monitorization of several devices are achieved with radio frequency transmitter to connect large numbers of devices to 1 central server.  This allows for a real time monitoring of dissolved oxygen, salinity, water level, temperature, pressure, position or live video.

The fully composite structure assures a rust free, low maintenance lifespan. No part of the structure requires painting at any stage of the product’s life span. The WG can be supplied in all I.A.L.A. colors.


Consult Specifications tab for detailed information.


Isophthalic NPG Polyester resin reinforced with Kevlar and glass fiber; 316-grade SS fixtures.

Mass (Kg | lb)

26 | 57,3

Volume (l | gal)

65,45 | 17,29

Width (mm | in)

500 | 19,7

Height (mm | in)

300 | 13,8

H max (mm | in)

800 | 31,50

Reserve Buoyancy (kg | lb)

52,4 | 115,5

Nominal Draft (mm | in)

120 | 4,72

Focal Plane Height (mm | in)

300 | 11,8

Total Float Volume (L | gal)

26,2 | 6,9

Maximun Mooring Load (kg | lb)

15,7 | 34,6

Safe Working Load, 1pt (kg|lb)

200 | 441

Submergence  (kg/cm | lb/in)

0,21 | 0,46

Visual Area (mt2 | ft2) (no signs)

0,1 | 1,1

Water Area (mt| ft2)

0,4 | 4,3

Wall Thickness (mm | in)

from 5 to 7 | 0,20 to 0,28

Ballast (kg | lb)

13,1 | 28,9

Available Colours

In accordance with I.A.L.A. recommendations.

Product Life Expectancy (years)


Intellectual Property Trademarks

Water Guardian and Marker Guardian are a registered trademark of Composite Solutions, Lda..

Quality Assurance

ISO 9001:2008

Warranty (years)


Standard Equipment

Data logger with Bluetooth connectivity with upgradability up to 32 sensors

32Gb of data storage

LCD display

Adjustable measuring time intervals

Optional Equipment

Temperature, humidity, wind & pressure Kit

Electrical conductivity, temperature & depth sensor Kit

Wi-Fi, VHF, Iridium, RF, GPRS, 3G & 4G


Dissolved Oxygen Kit

Wi-Fi, VHF, Iridium, RF, GPRS, 3G & 4G

Surveillance camera/motion sensor Kit

Solar Panels

Upgraded battery capacity

Status light