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SeaBones Calcium Reactor v2
SeaBones Calcium Reactor v2
SeaBones Calcium Reactor v2

SeaBones Calcium Reactor v2

13 reviews
$ 469.99 $ 329.99



Balanced replenishment of calcium and alkalinity is among the most important water quality corrections required for a thriving reef aquarium.  The SeaBones calcium reactor achieves this by liberating calcium and bicarbonate ions from aragonite media, typically old coral skeletons, using CO2 gas.  This process yields equal amounts of calcium and alkalinity added to your aquarium water with no by-product ions, unlike with two-part A/B solutions, which can throw off your system's ionic balance.

Once the reactor is installed and set to meet the calcium and alkalinity demands of your aquarium, it is a very hands-off system for continuous addition of these needed elements.  Since it operates continuously, calcium and alkalinity are added at exactly the rate they are taken up, resulting in very stable water chemistry parameters.  This is essential for the health of sensitive corals like Acropora sp. (SPS, aka Stability Promotes Success).  Again, this is unlike two-part solutions, which are often added all at once, causing a spike in calcium and alkalinity levels on a daily basis.

Back by popular demand (and some of you have been asking for a long time), our new version 2 SeaBones reactor takes advantage of the efficient design we developed for our Mutiny Ozone reactor, using a low power draw Sicce syncra pump to quietly and rapidly recycle seawater through a carbon dioxide internal atmosphere.  The coral bones media effectively acts as a diffusion chamber, creating a large surface area for CO2 to dissolve into seawater and react with the media.

Keeping the system simple, we selected a very tiny and energy efficient 12v DC feed pump, and matching drip nozzle that automatically sets the flow through rate at an ideal and consistent level.  This small pump is still capable of building significant internal reactor pressure, useful for helping dissolve CO2 into seawater.

Technical Data

Footprint with connected optional secondary media chamber: 12" x 7" x 21" tall.  Without the secondary chamber, the footprint is 7" x 7".

The secondary reactor chamber can be placed remotely for more flexible footprint options.

What's Included

Comes with main reactor, recirculating pump, feed pump, drip nozzle for flow control, and CO2 check valve.  The secondary chamber pictured with the main reactor is optional.

4 feet of tubing for reactor hook up are included, all CO2 safe tubing for water connections is included.

What's needed

A CO2 cylinder and regulator with bubble counter are required for operation but must be purchased separately.  We recommend the Aquarium Plants' Carbon Doser CO2 regulator.

We recommend chunky "coral bones" style calcium reactor media, such as Two Little Fishies' Reborn media.

Installation Guide


Customer Reviews
4.9 Based on 13 Reviews
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Ivan B.
United States United States
SeaBones Calcium Reactor v2

Awesome reactor and great support to help set it up in my unusual scenario! (reactor above the sump) I am using Kamoer to push feed water into reactor.

Daniel M.
Canada Canada
Seabones in Canada

This reactor arrived here in Canada fast, and in one piece. Well built, solid, and well finished. Set up way easy, appreciate having everything you would need together - feed pump, zipties, o-ring lube... The reactor is gnarly. Perfect size for my system, holds 1 big bag of Reborn media between the main and secondary chamber. Runs silent, awesome Ph probe holder, and c'mon - it just looks cool. Going to look through and see what other things I can snag from Avast.

Joe C.
United States United States
Shipping problems

Staff is very friendly and helpful. Received both the main chamber and second chamber broken. second chamber was destroyed. Replacement second leaked. Third was fine. Main chamber glued back together and leaked slightly before being reglued again and now works fine. Other than that unit works well.

Avast Marine Works SeaBones Calcium Reactor v2 Review
Michael O.
United States United States
SeaBones Calcium Reactor v2

Easy set up. Running at 2 bubbles per second and getting 18 DK in effluent, which keeps up with my current coral load. I am sure I could get a lot more if I started cranking up the CO2, but not necessary right now.

Andrew L.
United States United States
Seabones Reactor

Should have bought this along time ago, very easy to get up and running