Publicidad
Idiomas disponibles
Idiomas disponibles
Operation Manual ENG
Reactor for supplying reef aquaria with "Kalkwasser".
With the purchase of this unit, you have selected a top quality product. It has been specifically designed for
aquaristic purposes and has been tested by experts. With this unit, you are able to adjust the calcium level as well
as the carbonate hardness in your saltwater tank efficiently and to keep it to an optimum level.
1. Theory
What is Kalkwasser?
The addition of a saturated solution of Calciumhydroxide was the first method for supplying reef aquaria with
Calcium. Powdered Calciumhydroxide is stirred into tap or reverse osmosis water, the undissolved hydroxide
settles down and the clear supernatant is slowly added to the aquarium. This clear solution is called „Kalkwasser"
or lime water. Because of its high pH of 12.4, a dripwise addition is required to avoid a dangerous rise of the pH
value in the aquarium. This solution attracts carbondioxide from the air. This results in the formation of calcium
carbonate that is hardly soluble and precipitates. The calcium content of the Kalkwasser decreases. If the pH value
from the Kalkwasser decreases from 12.4 to 12.2, the calcium content drops from 900 to 300 ppm. The entrance
of carbon dioxide into the solution has to be avoided as far as possible.
If you measure the carbonate hardness or the alcalinity of a Kalkwasser–solution, you will find a very high value.
This value is, however, not caused by bicarbonate or carbonate ions which can be used by the corals but by
hydroxide-ions. The hydrochloric acid in the alcalinity test cannot differ between these substances. In the
-
-
aquarium, the hydroxide reacts with dissolved carbondioxide to form bicarbonate (OH
+ CO
= HCO
) – if dosed
2
3
slowly. If you dose the Kalkwasser too fast, the hydroxide may react with bicarbonate to form calcium carbonate
2+
-
-
– which is almost unsoluble. As a result, the alcalinity drops (Ca
+ HCO
+ OH
= H
O + CaCO
). For this reason,
3
2
3
it is recommended to add the Kalkwasser during the night when you find the lowest pH value and the highest
carbondioxide concentration.
An important advantage of the so-called "Kalkwasser-method" is the precipitation of phosphates. By this process,
almost unsoluble hydroxylapatite is formed:
3 Ca
(PO
)
. Ca(OH)
= Ca
(PO
)
(OH)
3
4
2
2
10
4
6
2
This substance will not dissolve under "normal" aquarium conditions.
2. Working principle of the reactor
The unit is filled with tap or reverse osmosis water and Calciumhydroxide (Kalkwasserpowder, approx. 2 cups).
The internal stirrer is started and the insoluble Calciumhydroxide forms a sediment at the bottom. Here, it is mixed
with the inlet water. Now, you can pump water with a small external pump (e. g. Niveaumat or dosing pump SP
3000) through the reactor. This pump is operated by a level controller or a time switch. The water flowing into
the reactor is enriched with calcium as it is pumped through the Calciumcarbonate sediment. As the flow rate is
slow, the undissolved Calciumcarbonate settles and you always have a clear solution of Calciumhydroxide at the
outlet. This principle allows a very compact construction. The reactor is hermetically sealed, carbon dioxide can
enter the reactor only with the inflowing water. By this, an interval of several weeks between 2 fillings is possible.
This interval depends on the calcium requirement of the aquarium. For refilling the reactor, the used liquid is
drained and fresh Calciumhydroxide is added. Afterwards, the reactor is filled with freshwater and the stirrer is
started. If the solution has cleared up, the unit is ready to go.
Inlet:
Only top up water to replace the evaporated water in the aquarium is supplied through the Kalkwasserstirrer. If
the tap water is of good quality (nitrate, phosphate) tap water can be used. But it is recommended to prepare the
tap water with a reverse osmosis unit, e. g. Aqua Medic easy line, premium line or platinum line. This refill water
is placed in a reservoir (canister or glass tank).
Now, the inflow (7) can be connected to the reservoir via a suitable pump. We recommend to use a peristaltic
pump (dosing pump SP 3000) or the Niveaumat with integrated level control.
6
Publicidad
