Pacific Sun’s new Sentry Auto-Top-Off System

By Leonard Ho 6 years agoNo Comments


Pacific Sun introduced their Kore 5th Intelligent Dosing System last year, which proved to be one of the most intelligent and capable dosers on the market.  But not all aquarists need advanced dosing systems; some of us just want a reliable way to top off evaporated water.

Optical sensor
Optical sensor

Enter Pacific Sun’s new Sentry ATO, a standalone auto-topoff system.  The Sentry ATO is available in two different models: one with a silent-running DC pump and another with a solenoid for use with direct connections to RO systems.  Both options feature a small control box with a programmable button (for fill and alarm adjustments), an optical water sensor, tubing, and acrylic mounting brackets for all of the aforementioned.

The optical sensor is specially designed and reportedly sensitive to 2-3mm water level.  Instead of the sensor being pointed vertically down, Pacific Sun design a horizontal optical sensor with a 90 degree prism; This clever design prevents water droplets accumulated at the bottom of sensors from interfering with readings.

Pacific Sun also incorporated some important safety features.  The sensor reads the water level every 5 seconds; should the water fail to achieve the desired level after 20 read cycles, the Sentry ATO will shut down the pump/solenoid while sounding an alarm to notify the aquarist the top-off reservoir or water supply is dry (or there is another problem).  The alarm can also be programed to sound if the water level is too high.


The Sentry ATO is now available for preorder from authorized Pacific Sun dealers for 79.90€ ($94-99 USD).


Additional Photos

Sentry <a class=ATO system” src=”sentry2.jpg/image_full”>
Sentry ATO system

DC pump option
DC pump option

Solenoid option
Solenoid option

  Advanced Aquarist

 Leonard Ho

  (1698 articles)

I'm a passionate aquarist of over 30 years, a coral reef lover, and the blog editor for Advanced Aquarist. While aquarium gadgets interest me, it's really livestock (especially fish), artistry of aquariums, and "method behind the madness" processes that captivate my attention.

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