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Reef Octopus

Reef Octopus CR100 Calcium Reactor


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Quality, design and affordability define the Octopus Calcium Reactor series. Available in 3 different models that feature reverse flow water current for maximum water and CO2 contact time with the coral media. All models come with PH probe holders to monitor Ph levels in the main reactor chamber and built in bubble counters to monitor CO2 drip rates. To help you meet the challenging task of maintaining alkalinity, calcium and trace elements , consider adding a Reef Octopus calcium reactor to your aquarium system.

How it works
A calcium reactor is essentially a chamber full of aragonite, which is the crushed skeleton of ancient hard corals. Aquarium water is pumped through this chamber along with pressurized carbon dioxide (CO2). The CO2 lowers the pH in the chamber to an acidic level which dissolves aragonite media into the aquarium water. In addition to dissolving the calcium, this process also dissolves nearly all the minerals and trace elements the coral used in order to grow.

Automated Calcium and Alkalinity supplementation - When set up properly and used correctly, a calcium reactor can maintain or increase calcium levels with little to no maintenance.

Rated for Aquariums up to 150 Gallons
Footprint: 9.5" x 7.5" | Body Diameter: 4" | Height: 20" 
Recirculation Pump: OTP 1000

- Reverse flow and CO2 Recirculating Design
- Auto Fill Bubble Counter
- Probe Holder w/Plug*
- Easy to Remove Lid
- Precision Effluent Control Valve
- Solid Construction
- 1/4"quick connect fittings
- 1-year Manufacturer`s Pump Warranty
* Does not include PH probe.

Calcium/Alkalinity Demand
- 150 Gallon – Light Demand | 125 Gallon – Medium Demand | 90 Gallon – Heavy Demand

Technical Specs
- Body Size: 4" 
- Footprint: 9.5" x 7.5"
- Total Height: 20"
- Inlet Size: 1/4"
- Max Feed Rate: 150 GPH
Note: Suggest a feed pressure slightly higher than a full flowing influent

Recirculation Pump Information
OTP 1000
Wattage: 13w

Warranty - 1 year manufacturer`s warranty on pump and 1 year on reactor body
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9 Questions
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will this calcium reacto run my 210 gallon reef.
If it's not a goinf to run it cause its to small please be truthful Thanks
Asked : May 22, 2017
By : Eddie, Hialeah FL
You are correct. This calcium reactor would not be able to keep up with your calcium demands in that size tank. Calcium/Alkalinity Demand - 150 Gallon – Light Demand | 125 Gallon – Medium Demand | 90 Gallon – Heavy Demand
Answered : Apr 25, 2018
By : Felicia
Does this make the water more alkaline when i generate calcium?
My time is limited and don't have alot. of time to constantly check water to make sure a machine is not adding things I don't want i add calcium without a reactor i don't want to have a reactor if I have to watch it for other things besides calcium levels..
Asked : Jan 09, 2017
By : Seabear, Illinois
Great Question. A calcium reactor increases both your calcium and alkalinity levels. If you add a product such as the Brightwell Aquatics NeoMag to the chamber, it will even add magnesium.
Answered : Jan 09, 2017
By : MD Tech
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Overall, others give this:

  • 4.5

2 Reviewers (100%) would recommend this

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Easy to set up
Good price, fast setup, Nice foot print
Horrible instructions, cheap effluent valve
This was smaller than I thought it would be. I have an original cr-100 and it is much larger can hold 8# of media. This one maybe 4#. My old one however was just that old and needed to be replaced.
The set up on this was much easier than any other reactor I have had and it works. This is on a h...Read More
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Good calcium reactor. Smallish footprint. I'm running it on a medium stocked SPC 110G tank and do not have to use 2-part. Setup was WAY easier than my old Korallin reactor. Please note also these no longer come with the OTP pumps they come with aquatrance pumps. Overall would buy again and would...Read More
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Overall, others give this:

  • 4.5

2 Reviewers (100%) would recommend this

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CV21043 Reef Octopus CR100 Calcium Reactor // Reef Octopus OutOfStock 299.99 USD 4.0 1