The IceCap Kalk Stirrer is the first new version of this device we’ve seen in the aquarium hobby for way too long. Adding a concentrated solution of Calcium Hydroxide (CaOH), also known as Kalkwasser, was one of the first forms of dosing and mineral replenishment in the reef aquarium world.
The popularity of Kalkwasser has waxed and waned over the years but more recently we’re seeing a big resurgence of reef aquarists taking care to keep pH high, and there’s no better way to do that than with regular additions of kalkwasser. However unlike every other additive and chemical we add to manage reef aquarium water, the super high pH of requires it to be mixed on a regular basis, this is where kalk stirrers come in.
There’s several approaches to mixing calcium hydroxide with pure freshwater to create limewater; these include a top mounted motor connected to a stirrer bar, as in the Avast Marine K1, driving a irrigation spinner with high pressure like the Two Little Fishes KW300, but the most classic approach is using a magnetic stirrer such as in the new IceCap Kalk Stirrer Reactor.
The IceCap Kalk Reactor takes a very conservative approach to its design, choosing to nail the basic features in a familiar and approachable construction. A basic cylinder sits atop the motor box, with an inlet for pure fresh water, an outlet for saturated limewater, a completely removable lid for easy access and cleaning, and a removable cap for simple topping off of the Calcium Hydroxide powder.
Despite the pretty straightforward build and design, there’s a couple details that could be improved to increase the durability and performance of the IceCap Kalk Stirrer. For starters the power connector to the motor box of the stirrer is somehow not only not covered or waterproofed, it’s completely exposed which will leave it vulnerable to inevitable corrosion around the humid environment of a reef aquarium, especially when salt is combined.
The entire point of a kalkreactor, the reason you need to use a sealed chamber like a kalkreactor, is because the calcium hydroxide in the water combines with carbon dioxide in the air, to create a calcium carbonate crust. This precipitation essentially negates both the calcium and hydroxide we are trying to add to our aquariums and as it builds up at the surface, it clogs up the effluent line.
Most Kalkreactor designs either have a wide diameter effluent line, an elbow to direct subsurface limewater out of it, or both. IceCap chose to go with a 0.25 inch diameter for the effluent but since we prefer the added safety, it was simple enough to simply glue in an elbow after drilling a small hole to prevent any potential siphon from starting.
Despite these few details, the IceCap Kalk Stirrer performs the job of mixing the calcium hydroxide and freshwater into a calcium-rich, pH boosting limewater generator. Coupled with the Kamoer X1 dosing pump IceCap’s new Kalk Stirrer is a really important tool for boosting pH in any reef tank and there’s a good reason this was the first successful method aquarists used to supplement coral growth in the mini reef aquarium. [CoralVue]