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SRO Kalk Stirrer Nilsen Reactor

SRO Kalk Stirrer Nilsen Reactor

Product Code: oct-ks100


We currently have 1000 in stock.

Regular price $225.00 Sale


Reef Octopus new 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. Our Kalk Stirers are designed to keep the undissolved particles at the bottom of the reactor chamber while always leaving the clear highly saturated kalkwasser liquid at the top. Adding kalk powder couldnt be easier with just a few twists of the large thumb screws releasing the seal-tight lid for quick and easy kalk refills.

No need for pesky powerheads that randomly need to be cleaned or replace and no more risky dosing with large vats of lime water which take up valuable space. You will never have to worry about premixing or clogs again when using our new innovative and efficient Kalk Stirrer (Nilsen Reactor) which are extremely easy to use and salt-water safe, making them simply the most economical and best kalk reactor out there.

Item #: KS100

Dimensions: 5x5x24H

Kalk Stirrer Instructions for motorized SRO Kalk Stirrer


The addition of a saturated solution of Kalkwasser is considered the first method of supplying the reef aquaria with Calcium and Alkalinity while maintaining a high PH. Your new Octopus Kalk Reactor gently stirs powdered kalkwasser into RO/DI water creating a clear super saturated form of Lime water aka Kalkwasser. Due to its high pH of 12.4 a slow addition is required to avoid a dangerous rise of the pH value in the aquarium. An important advantage of the so called Kalkwasser-method is the precipitation of phosphates.

Setup Instructions for Reef Octopus Kalkwasser Reactor/Stirrer

1.Place the reactor in a location where the outlet is higher than the sump. The quick connect outlet is where the kalkwasser will drip from and typically hung over the sump in a high flow area away from any pumps. The output must flow downhill to the sump area.

2.Connect the feed pump from your top off container to the Kalkwasser reactor with 1/4 RO tubing. Peristaltic pumps are preferred due to the high level of accuracy and anti siphon characteristics. (If you are using a peristaltic pump then skip to step #4)

3.If you are using a feed pump like Toms Aqualifter then the input tubing should be placed in your reservoir with RO/DI water. Connect the outlet of the pump to a short piece of 1/4 tubing and install a tee fitting with one end securely mounted several feet above the water level of your top off reservoir and the other going to the reactor. The tee is placed in the line to create a siphon break. You may also use a small pump such as a maxijet modded with a fitting on the output to feed water to the reactor. You will have to use a check valve in the line to prevent any back siphoning into your reservoir.

4.The Kalkwasser reactor should be filled 2/3 of the way with RO/DI water.

5.Add enough kalk powder to fill the reactor with approximately 3/4 1cup of kalkwasser. The idea is that the twin blades create a slow motion that gently disrupts the the kalk in to solution. (Too much kalk will place stress on the motor and can cause pre-mature failure) Allow the solution to settle for 15 minutes prior to turning the reactor on. Now you are ready to plug the reactors transformer into a power source and begin to dose saturated Kalkwasser to your aquarium. The stirrer should be set on a controller to run ever 2 hours for approximately 15 minutes. Do not run these units 24/7.


Fresh Kalkwasser powder should be added to the reactor every 2-3 weeks by removing some of the water within the reactor prior to adding the kalk powder. The whole reactor should be rinsed clean with hot water about every month to prevent any build up and to remove what doesnt dissolve into saturated lime water. Every six months the reactor should be removed from the system and cleaned with vinegar and rinsed well before re-installing the unit.

Common ways of automating your top off/Kalkwasser dosing

1.Via ATO- Simple plug your feed pump to the ATO (Auto Top Off) Units controller and saturated kalk will dispense when your tank need replenishment after evaporation.

2.Via Timer or Controller- Estimate your daily evaporation and the time it takes for the pump to replenish the levels (remember that Seasonal changes will change your systems evaporation rate and the setting will have to be adjusted.) To avoid flooding, you should calculate a safety reserve and replace only two third of the evaporated water with Kalkwasser. This time is adjusted at the time switch. It is also possible to dose in several intervals to avoid a pH increase. It ideal, if you add the Kalkwasser during the night, when the pH in the aquarium drops.