Description

Plagron CalMag Pro 500 ml – liquid fertilizer with calcium and magnesium for RO and soft water

CalMag Pro by Plagron is a liquid additive from the UNIVERSAL line that supplements calcium and magnesium in reverse osmosis (RO) water and soft water. A deficiency of these two elements is a well-known problem in such water, which is why CalMag Pro serves as the base for preparing a nutrient solution with a balanced mineral concentration.

The product contains calcium and magnesium in a ratio selected so that the two ingredients do not compete with each other during uptake by the plant. Some calcium and magnesium fertilizers cannot be mixed due to sulfates – here, both elements are contained in a single product.

The 500 ml bottle is enough to prepare at least 500 liters of water at the maximum dose of 1 ml per liter.

Key features

  • supplements calcium and magnesium in RO and soft water
  • useful for growing under LED lights, where plant transpiration is lower than under traditional lamps, making calcium and magnesium uptake more difficult
  • strengthens cell walls and gives plants a stiffer, stronger structure
  • supports the development of young roots and more efficient nutrient uptake through root hairs
  • NPK 5-0-0 fertilizer with calcium and magnesium in one bottle
  • efficient concentrate: maximum 1 ml per liter of water

Composition and NPK analysis

NPK 5-0-0 fertilizer with calcium and magnesium. Nutrient content according to the manufacturer's technical data sheet (% w/w):

  • total nitrogen (N): 5.1% – entirely nitrate nitrogen
  • calcium oxide (CaO): 5.7%, corresponding to approximately 4.1% calcium (Ca)
  • magnesium oxide (MgO): 3.3%, corresponding to approximately 2% magnesium (Mg)
  • concentrate pH 4.3, EC 128 mS/cm, density 1.26 g/ml

Application

CalMag Pro supplements calcium and magnesium in reverse osmosis filter water and soft water used to prepare a nutrient solution – regardless of the growing medium, for indoor and greenhouse cultivation, especially under LED lighting. It is useful for all plants watered with such water, from houseplants and tropical plants to vegetables, herbs and ornamental plants; it is usually not needed with hard tap water. Apply the additive with every watering as the base of the prepared nutrient solution.

How to use

  1. Shake the bottle well before use.
  2. Add a maximum of 1 ml of the product per 1 liter of water (1:1000).
  3. Use the prepared water every time you water the plants.

For reverse osmosis water, the manufacturer recommends 0.75 ml per liter, resulting in an initial EC of 0.4 mS/cm.

Safety and storage

Store and transport at a temperature of 0–35°C; protect from frost and direct sunlight. When unopened, the product remains suitable for use for 4 years from the production date. Avoid contact between the concentrate and the eyes or skin; in case of contact, rinse the eyes or skin with plenty of water. Keep out of reach of children and animals; do not ingest.

Product information

  • Capacity: 500 ml
  • Form: liquid, clear, blue, odorless
  • NPK: 5-0-0
  • Calcium and magnesium: CaO 5.7%, MgO 3.3%
  • Dosage: up to 1 ml per 1 L of water
  • Line: Plagron UNIVERSAL
  • Manufacturer: Bertels B.V. (Plagron), the Netherlands

Plagron CalMag Pro 500 ml is a simple way to supplement calcium and magnesium in soft or filtered water used to prepare a nutrient solution for plants.

Product form

Plagron CalMag Pro 500 ml – calcium and magnesium fertilizer for RO and soft water

500 ml 50,60 zł 1 L 78,90 zł

50,60 zł

    • Fast shipping within 24 hours
    • Premium quality

    Description

    Plagron CalMag Pro 500 ml – liquid fertilizer with calcium and magnesium for RO and soft water

    CalMag Pro by Plagron is a liquid additive from the UNIVERSAL line that supplements calcium and magnesium in reverse osmosis (RO) water and soft water. A deficiency of these two elements is a well-known problem in such water, which is why CalMag Pro serves as the base for preparing a nutrient solution with a balanced mineral concentration.

    The product contains calcium and magnesium in a ratio selected so that the two ingredients do not compete with each other during uptake by the plant. Some calcium and magnesium fertilizers cannot be mixed due to sulfates – here, both elements are contained in a single product.

    The 500 ml bottle is enough to prepare at least 500 liters of water at the maximum dose of 1 ml per liter.

    Key features

    • supplements calcium and magnesium in RO and soft water
    • useful for growing under LED lights, where plant transpiration is lower than under traditional lamps, making calcium and magnesium uptake more difficult
    • strengthens cell walls and gives plants a stiffer, stronger structure
    • supports the development of young roots and more efficient nutrient uptake through root hairs
    • NPK 5-0-0 fertilizer with calcium and magnesium in one bottle
    • efficient concentrate: maximum 1 ml per liter of water

    Composition and NPK analysis

    NPK 5-0-0 fertilizer with calcium and magnesium. Nutrient content according to the manufacturer's technical data sheet (% w/w):

    • total nitrogen (N): 5.1% – entirely nitrate nitrogen
    • calcium oxide (CaO): 5.7%, corresponding to approximately 4.1% calcium (Ca)
    • magnesium oxide (MgO): 3.3%, corresponding to approximately 2% magnesium (Mg)
    • concentrate pH 4.3, EC 128 mS/cm, density 1.26 g/ml

    Application

    CalMag Pro supplements calcium and magnesium in reverse osmosis filter water and soft water used to prepare a nutrient solution – regardless of the growing medium, for indoor and greenhouse cultivation, especially under LED lighting. It is useful for all plants watered with such water, from houseplants and tropical plants to vegetables, herbs and ornamental plants; it is usually not needed with hard tap water. Apply the additive with every watering as the base of the prepared nutrient solution.

    How to use

    1. Shake the bottle well before use.
    2. Add a maximum of 1 ml of the product per 1 liter of water (1:1000).
    3. Use the prepared water every time you water the plants.

    For reverse osmosis water, the manufacturer recommends 0.75 ml per liter, resulting in an initial EC of 0.4 mS/cm.

    Safety and storage

    Store and transport at a temperature of 0–35°C; protect from frost and direct sunlight. When unopened, the product remains suitable for use for 4 years from the production date. Avoid contact between the concentrate and the eyes or skin; in case of contact, rinse the eyes or skin with plenty of water. Keep out of reach of children and animals; do not ingest.

    Product information

    • Capacity: 500 ml
    • Form: liquid, clear, blue, odorless
    • NPK: 5-0-0
    • Calcium and magnesium: CaO 5.7%, MgO 3.3%
    • Dosage: up to 1 ml per 1 L of water
    • Line: Plagron UNIVERSAL
    • Manufacturer: Bertels B.V. (Plagron), the Netherlands

    Plagron CalMag Pro 500 ml is a simple way to supplement calcium and magnesium in soft or filtered water used to prepare a nutrient solution for plants.

    Frequently Asked Questions - FAQ

    Do you ship orders to the entire European Union?

    Yes, we ship to all countries in the European Union. The cost and delivery time depend on the destination country, the chosen shipping method, and current logistical conditions.

    Can I pay cash on delivery (COD)?

    Cash on delivery is available in selected European Union countries. Available payment methods are always displayed during the checkout process, depending on the delivery country.

    Where can I find sowing and cultivation instructions?

    Instructions and guides on sowing and plant care can be found in the product descriptions and on our blog, where we regularly publish educational materials. Additionally, we include a printed instruction manual with every order.

    Are the seeds sold legal and safe?

    Yes, all products offered by Mr.seed are legal and marketed in accordance with applicable regulations and the guidelines of phytosanitary institutions.

    Where do the seeds come from?

    Our seeds come from trusted producers and direct sources around the world. We collaborate with plantations, botanical gardens, and experienced seed collectors.

    How quickly are orders shipped?

    We ship most orders on the same or next business day. During busy periods, such as peak season or holidays, processing time may extend up to 72 hours.

    Where can I find answers to more questions?

    You can find an extensive database of answers on the full FAQ page, where we cover in detail topics such as orders, shipping, payments, cultivation, and products.

    👉 [Go to the full FAQ]

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