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Reef Octopus

Reef Octopus CR100 4" Calcium Reactor

Maintain the calcium and alkalinity in your reef tank with CR100 Calcium Reactor from Reef Octopus.

  • Rated for aquariums up to 150 gallons
  • Reverse flow and CO2 recirculating design
  • Aquatrance 1200 Pump
  • pH probe holder included (probe sold separately)

A calcium reactor is used to maintain a balanced amount of calcium and alkalinity in your reef tank. In order to use a calcium reactor, you will need a CO2 regulator, CO2 tank, pH probe/controller, small feed pump (flow rate should be set 1-2 liters per hour) and calcium reactor media.

Filtration Handling

Well Stocked Tank - Rated up to 90 gallons

Medium Stocked Tank - Rated up to 125 gallons

Light Stocked Tank - Rated up to 150 gallons


  • Reverse flow design
  • Control the reactor with CO2 needle valve and the effluent valve
  • Auto fill bubble counter
  • pH probe holder
  • Easy to remove lid
  • Precision effluent control valve
  • Solid construction
  • 1/4" quick connect fittings


  • Body Size: 4”
  • Foot Print: 9.5” x 7.5”
  • Total Height: 20”
  • Media Capacity: 1.7L
  • Inlet Size: 1/4"
  • Max Feed Rate: 150 GPH
  • Suggested feed rate is slightly higher than a full flowing influent

Aquatrance 1200 Pump Features:

  • Quiet operation
  • Power Consumption: 15 Watts

Manufacturer's Warranty

  • 1 year on pump
  • 1 year on reactor body