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Calcium Reactors & Kalkreactors

Calcium Reactor
AquaMaxx Calcium Reactors
Uses an upflow design to mix saltwater, calcium carbonate and CO2 inside a reaction chamber to eliminate the need for daily two-part dosing. Computer-precision engineered and utilize the latest aquarium technology to deliver unparalleled performance and value.
Deltec Calcium Reactors
Media is kept constantly moving, so that it is impossible for channeling to occur and the whole of the media is utilized. Can achieve a dKh in excess of 80, which corresponds to a significantly higher calcium level.
Korallin Calcium Reactors
Our top-selling, highest-rated Calcium Reactor. Superior quality. The lowest CO2 consumption of any reactor, meaning less impact on lowering the pH of your aquarium.
Precision Marine Effluent Chamber
Attaches to any calcium reactor to help raise the pH of the effluent from your reactor.
Reef Octopus Calcium Reactors
If you are concerned about calcium levels due to your calcium loving animals look no further than our SRO calcium reactors
Replacement Eheim Pump
German made, top of the line internal or external water pump.
ViaAqua Acro-Cal Calcium Reactor
Offers a simple and convenient solution for maintaining calcium and alkalinity in your reef tank.
Kalkwasser Reactor
Precision Marine Kalkreactor
Master fabricated and computer cut, the KR620 is a very nice piece of equipment. One of the best ways to add kalkwasser to your aquarium. No additional supply pump, and is operational with minimum water level.
Two Little Fishies KW Reactor 300 (Kalkwasser Reactor)
Creates saturated kalkwasser solution every time the feed pump is switched on to replenish evaporated water. Gentle mixing is achieved with a rotating sprinklerhead that is "powered" by the pressurized water feed. For aquariums up to 300 gallons.
Reef Octopus Kalkwasser Reactor
Reef Octopus Kalk Stirrer (Nilsen Reactor) carries a high torque low RPM motor that effectively, silently and gently mixes your calcium hydroxide (kalkwasser). This method is not only ideal but is also the safest way of dosing the freshest possible kalkwasser to your reef system.
Calcium Reactor Media and Kalkwasser
Brightwell Aquatics Neo-Mag Magnesium Media
High-purity, magnesium-rich mineral for traditional calcium reactors, or even blended in to pre-existing aquarium substratum, to gradually increase and maintain the magnesium concentration in the system.
CaribSea Calcium Reactor Media
A complete reactor media containing not only calcium and carbonate, but essential trace elements as well.
Korallen-Zucht ZEOvit Reactor Media
Zeolite - three different sized untreated and all natural Zeoliths of highest quality. ZEOmag Magnesium Granulate - pure magnesium granulate
Two Little Fishies ReBorn Coarse Aragonite Calcium Reactor Media
Composed of fossil skeletons of reef building corals sustainably harvested from pristine sites in the Western Pacific. Replenishes calcium and carbonate alkalinity, strontium and trace elements.
Kalkwasser (Calcium Hydroxide)
"Kalkwasser" is the German term for limewater, a saturated solution of calcium hydroxide in water. We have a variety of calcium hydroxide supplements available to help build your reef.
A calcium reactor is a simple, convenient solution used to maintain calcium and alkalinity in a reef aquarium. They require little maintenance after the initial setup and are almost a necessity for tanks heavily stocked with stony corals, where calcium and alkalinity demands are high.

To remove any guesswork, we’ve assembled several packages that include everything you’ll need: a calcium reactor, a CO2 Regulator with a needle valve, media, and a CO2 Tank. The Aqua Lifter pump is a very useful—and very affordable—accessory that will feed your calcium reactor with water (although this is not necessary for general operation).

Calcium reactor lines favored by Marine Depot customers include Korallin, KNOP, AquaC RX-1 and Precision Marine.

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