CalMag Pro 5-0-0

The solid base for RO water and soft water

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Product information

A shortage of calcium and magnesium (Ca/Mg) in reverse osmosis (RO) water and soft water is a well-known problem. CalMag Pro ensures that a balanced concentration of minerals is available in the water. This is the solid base to start creating your nutrient water. CalMag Pro is mainly used with RO water and soft water.

CalMag Pro contains the optimal calcium and magnesium ratio to prevent competition between the two nutrients. Some magnesium and calcium fertilisers are not mixable due to sulphates, but CalMag contains both elements in perfect proportion.

Dosage and use

Add a maximum of 1 ml CalMag Pro per 1 litre of water (1:1000). Use this solution each time the plants are irrigated.

CalMag ProNPK

NPK fertiliser (5-0-0).
Ca: 4.1%
Mg: 2%


1 L bottle and 5 L, 10 L & 20 L cans.

Some sizes may not be available in all countries. 

We recommend a quantity of 0.75 ml per litre of RO water to achieve an ideal starting EC of 0.4.

With LED lamps, plant transpiration is lower than with traditional lamps. This disadvantages the absorption of calcium and magnesium. By adding CalMag Pro, you compensate for the reduced transpiration.

CalMag Pro strengthens cell walls. By connecting different essential molecules, the plant gets a rigid structure that improves resistance.

The use of CalMag Pro promotes young root growth, allowing the root hairs to absorb nutrients more efficiently.


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