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The kalk stirrer utilities the maxijet pump provided to draw water from the reservoir, and then pushing the affluent back to the sump or aquarium.

Also due to its pressurised design allows you to sit the reactor below the water level ... allowing the kalk reactor to sit in the cabinet while pushing the affluent back to the raised aquarium above.

An 'easy refill' is fitted for ease of adding media without the need for removing the lid housing.

The Kalk Stirrer also comes with a built-in ball valve for easy adjustment of flow to the media... while the flow to the aquarium/ sump works independently.

Can be used in sump or cabinet.

Everything you need to get going... just add the Kalk.

The maxijet 500 is a Dual voltage pump and can be used with both 220v - 240v and 110v - 120v electrics.
Plug adapters maybe required to do so though.. as pumps come with uk plugs fitted.

Kit Consists Of :
Kalk Stirrer, Maxijet pump, Control Valves x 2 and 2m piping (6mm)

Dimensions (mm):

Height: 600


Column : 90

Hosetails: 4

  • Instructions

    Kalk Stirrer.
    The kalk stirrer setup couldn't be easier... its ready to go and you just need to add water and media.


    1. To do this just open the refill union and add water till the unit is full or near full (including piping).

    2. Sure black valves to both the upper hosetails (degas Valves) and one to the outlet hosetail (situated below the ball valve… then close all.

    3. Now open the filler union and fill with required amount on media.

    4. Secure piping to inlet hosetail (situated on the far elbow) and run piping to RO water container or similar and place piping in the water.

    5. Now open the degas valves and suck out all remaining air from the reactor and lid. Once achieved, close valves. 

    6. Now start the pump and adjust the ball valve till you get the right lift on the media.

    7. Open outlet valve to acheive desired drip rate. Check for air in the system and rid once more through the use of the degas valve. Its now set and periodically check water/ media levels and adjust to accommodate.


  • Instructions 2

    Kalk Stirrer


    Kalkwasser, (saturated limewater), is one of the oldest and most widely established methods of adding calcium to the reef

    aquarium first introduced by Peter Wilkinson a Swiss aquarist.

    Kalkwasser is made by dissolving calcium hydroxide powder in freshwater to produce a strongly alkaline saturated solution that

    contains free calcium and hydroxide ions. The solution however is highly reactive with CO2 in the air and must be produced and

    stored in airtight conditions to prevent a reaction forming insoluble calcium carbonate. The reaction with CO2 significantly reduces

    the free calcium ions from 900mg/l in the fresh solution at pH 12.4 to 5-6mg/l at pH 10.


    In addition to adding calcium, Kalkwasser also has the benefit of adding hydroxide ions, which react to neutralise organic acids in

    the aquarium that otherwise would exhaust the buffering capacity of the system. It also helps precipitate phosphates from the

    water, which fuel nuisance algae growth and inhibits calcification of stony corals and counters the natural tendency within the

    aquarium towards falling pH. Kalkwasser contains no other ions that would otherwise cause an imbalance in the water chemistry.

  • Instructions 3

    In order for the Kalkwasser Mixer to operate correctly it is necessary in addition to provide;


    1. A method of monitoring and replacing the evaporative loss within the tank

    2. A supply of freshwater (RO)


    Controlling Evaporative Loss.

    The loss of water from the aquarium system by evaporation is of fresh water only which increases the salinity within the aquarium

    This is normally replenished using a float switch and controller such as the Deltec Aquastat Type A, (Item number 90100).

    As the float switch rises and falls it switches the controller on and off, which in turn controls a pump or

    solenoid to top up the lost water.


    Options for Fresh Water Supply.


    Pumped Top Up: The conventional freshwater supply from a reservoir situated beside the sump or

    tank. The volume of the reservoir should be chosen such that it is allows a reasonable number of days between refilling.

    The volume of water that a mains supply RO unit can produce is infinite and therefore potentially disastrous to the aquarium. We

    would therefore always recommend that the there are at least three safety cut off devices operating on the system. These are:-


    Installation and General Operation of the Kalkwasser Mixer

    The Kalkwasser mixer can be positioned inside or outside of the sump or stood inside the freshwater reservoir. Fill the body full with R.O. water and add mix to about 1'2" depth. More powder can be added later if required after the solution has cleared.

    Start pump and open close valve to correct flow rate..... look for a drip rate of 1 drip per second and then increase and decrease over time to match requirments.


    Important: 1. - Care should be taken not to breath in the fine calcium hydroxide dust and also with the freshly mixed solution as it

    is caustic and will dissolve clothing or similar items. If you have prolonged contact with your skin or get any in your

    eyes flush well with copious quantities of fresh water.


    The Kalkwasser stirrer should stir the solution continuously 24-7 however it is possible to experiment with additions of Kalkwasser

    outside of the aquarium photoperiod, i.e. at night, to reduce the drop in pH which naturally occurs when photosynthesis stops.


    If Kalkwasser is administered in conjunction with a calcium reactor or evaporative cooler you must be careful not to overdose as

    the calcium may drop out of solution in the tank if its concentration gets too high. To alleviate this problem it is recommended that

    you create a further bypass so that fresh water can be added to the sump along with the Kalkwasser.

    Use of Kalkwasser with a plenum system must be carried out with great care as the sand bed may start to solidify due to formation

    of calcite if the calcium level gets too high. This will render the plenum inoperative.

    As the saturated solution within the mixer gets old the pH will fall due to reaction with dissolved CO2 from the supply water. For this

    reason it is recommended that the mixer is thoroughly cleaned out every 2 weeks or when ever the elevating effect on pH within

    the tank is seen to diminish. For this reason it is better to make regular small additions of calcium hydroxide powder rather than

    make one initial large batch. Take time whilst refilling to remove any calcium carbonate deposits and ensure that both vent holes

    and the outlet nozzle are clear. Fresh water reservoirs should be cleaned from time to time to prevent bacterial build up.

    For further information on this or any of our other product range please contact us on:

    01529 497076

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