NEPTUNE SYSTEMS DDR Dual Reservoir with Optic Sensors


The Neptune Systems DDR Dual Reservoir is used for 2-part (Alk/Cal), additives and other applications.

This attractive fluid containment system stores your dosing fluids in style and has an optical sensor that self-monitors the fluid level, and notifies you when it is time to refill.

  • Each side stores two liters (2L) of fluid
  • Connects directly to your DOS
  • Optical sensors inform your APEX when levels are low
  • Strong, cast-acrylic construction
  • Low-profile will not tip over easily
  • Easy to refill
  • Push-fit tubing connections

Big Volume

For most saltwater aquarium that require dosing Calcium and Alkalinity, the 2L (2000ml) amount is more than enough to last at least two weeks. If you were dosing other additives it might last months before needing a refill.

Easy to Refill. Stable.

The DDR has easy lift off lids that make refilling it super easy. The DDR was also designed to have a low center of gravity, hence it would not tip over easily.


The DDR is the only dosing container on the market that connects electrically to your DOS and uses optical sensors that alert you when your fluid has approximately 20% remaining.

This alert could be used to send you a text or an email, or even trigger other events on your Apex. Also, when detecting water level, optical sensors are far less likely to fail than their float switch counterparts.

Ready for Apex Fusion

Although not required, the DDR interfaces directly into your Apex Fusion dashboard. See in realtime your fluid levels and get an alarm when a reservoir runs low.


The specifications of Neptune Systems DDR Dual Reservoir:

  • Size (Approx.): 10.5-inch x 8.5-inch x 5.5-inch
  • Fluid Capacity (Approx.): 2000ml per side
  • Weight (Approx.): 2 pounds
  • Requires: Apex, Apex Lite, or Apex Jr. and DOS to operate sensors


  • DDR Dual Reservoir with Optic Sensor
  • 4m of DOS tubing