Neptune Systems DOS Dual Reservoir

The DDR (DOS Dual Reservoir) is a purpose-built liquid storage solution designed to integrate seamlessly with the Neptune DOS dosing system. Featuring two 2-litre reservoirs, built-in optical level sensors, and a low-centre-of-gravity design, the DDR is an elegant and highly functional upgrade for reefkeepers using two-part or additive dosing.

Monitor fluid levels in real time via Apex Fusion, and enjoy easy refills, secure tubing connections, and reliable operation in a compact, cast-acrylic enclosure.

Requires Neptune DOS and Apex Controller (A2 or A3 Series) to operate level sensors.

Key Features

• Total capacity of 4 litres – 2L per reservoir

• Designed to connect directly to the Neptune DOS

• Optical sensors provide real-time fluid level data in Apex Fusion

• Low-centre-of-gravity helps prevent tipping or spills

• Removable lids for quick, mess-free refills

• Push-fit tubing connectors for secure, leak-free dosing lines

• Built from high-quality cast acrylic

• Designed specifically for two-part or additive storage

Intelligent Integration

The DDR includes two built-in optical fluid level sensors, which provide:

• Real-time volume monitoring of each reservoir in Apex Fusion

• Low-fluid alerts, helping prevent dry runs and dosing inconsistencies

• Smooth integration with the Apex and DOS system via a single connection cable

Ideal For

• Two-part calcium and alkalinity dosing

• Additives such as magnesium, trace elements, or amino acids

• Reef tanks requiring precise volume monitoring and automation

Specifications

• Dimensions: 26.7 cm (L) x 21.6 cm (W) x 14 cm (H)

• Capacity: 2,000 mL per side (total 4,000 mL or approx. 1.05 US gallons)

• Construction: Cast acrylic

• Sensor Output: Requires Apex (Apex Pro, Apex, Apex Jr, or Apex Lite) and DOS

What’s Included

• 1x DOS Dual Reservoir (DDR) with pre-installed optical sensors

• 1x Sensor Cable (connects to DOS or Apex)

• 4 m of dosing tubing

• Getting Started Guide

Note: Requires a Neptune DOS and Apex Controller (A2 or A3 Series) to enable sensor feedback and integration.