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CANNA – CalMag Agent
£12.99 – £53.99Price range: £12.99 through £53.99 Inc VAT
Canna CalMag Agent increases water hardness and provide the right amount of calcium and magnesium, at the ideal ratio, for exceptional plant growth.
SKU: N/A Categories: Additives & Boosters, Nutrients & Additives Tags: calmag, calmag agent, canna calmag, canna nutrients
Description
CANNA – CalMag Agent
CANNA CalMag Agent is a high-quality calcium and magnesium supplement developed to optimise soft or low-quality water for hydroponic and soil-based growing systems. Designed by CANNA’s expert team of Dutch horticultural scientists, this powerful additive stabilises EC levels and enhances nutrient absorption, preventing common deficiencies that can stunt growth or reduce yields.
By improving water quality and nutrient balance, CalMag Agent ensures plants develop stronger cell walls, vibrant green foliage, and more robust flowering sites. It’s an essential supplement for growers using reverse osmosis (RO) water, rainwater, or soft tap water.
Key Benefits:
Corrects calcium and magnesium deficiencies in soft or RO water.
Improves nutrient uptake and overall plant health.
- Ideal 3:1 Calcium Magnesium ratio.
Enhances strength, colour, and growth rate.
Prevents blossom-end rot, leaf yellowing, and weak stems.
Stabilises EC and pH for consistent feeding results.
Instructions for Use:
Shake well before use.
Add 0.1–0.5 ml per litre of water to adjust calcium and magnesium levels until you reach an EC of 0.4.
Use during both vegetative and flowering stages as needed.
Monitor EC and pH after adding to ensure optimal nutrient balance.
- Can be used alongside any other nutrient range.
Find out how much you’ll need to get you through your grow cycle here.
Additional information
| Weight | N/A |
|---|---|
| Dimensions | N/A |
| Size | 1 litre ,5 litre ,10 litre |
About brand
CANNA is one of the world’s most trusted brands for plant nutrients, boosters, and growing media. Growers of all skill levels rely on these nutrients to produce strong, healthy plants and consistently high yields.
Backed by decades of research and scientific development, the brand focuses on purity, consistency, and precision. As a result, plants absorb nutrients more efficiently, leading to faster growth, improved resilience, and better overall performance.
CANNA Nutrient Ranges
CANNA offers dedicated nutrient lines for different growing methods, making it easy to match your feeding program to your setup.
- CANNA Terra – Designed for soil growing, offering simple and effective nutrient solutions
- CANNA Coco – Optimised for coco coir, supporting strong root development and vigorous growth
- CANNA Aqua – Ideal for recirculating hydroponic systems
- CANNA Hydro – Developed for run-to-waste hydroponic setups
In addition, CANNA’s additives — including RHIZOTONIC, PK 13/14, CANNAZYM, and Boost Accelerator — help improve root growth, nutrient uptake, flowering, and plant health.
Why Choose CANNA?
- Scientifically developed nutrients for consistent, reliable results
- Dedicated nutrient lines for soil, coco, and hydroponics
- High-quality additives to enhance growth, flowering, and yield
- Trusted by hobby growers and commercial cultivators worldwide
- Focus on efficiency, reducing waste while maximising plant performance
Popular CANNA Products
- CANNA Terra Vega & Terra Flores
A complete nutrient solution for soil growers, supporting both vegetative growth and flowering stages. - CANNA Coco A & B
A two-part nutrient designed specifically for coco coir, delivering balanced nutrition and strong plant development. - CANNA Boost Accelerator
A high-performance flowering stimulant that increases nutrient uptake, boosts metabolism, and helps produce heavier, higher-quality yields. - CANNA RHIZOTONIC
A powerful root stimulator that encourages rapid root growth, reduces transplant shock, and improves plant health.
Frequently Asked Questions
What is the difference between CANNA Terra, Coco, Aqua, and Hydro?
Each range is designed for a specific growing medium or system. Terra works with soil, Coco with coco coir, Aqua with recirculating systems, and Hydro with run-to-waste setups.
Do I need to use A & B nutrients together?
Yes, A & B nutrients work as a balanced two-part formula. Using both ensures plants receive all essential nutrients in the correct ratios.
What does PK 13/14 do?
PK 13/14 provides additional phosphorus and potassium during flowering, helping plants produce bigger, denser flowers and improved yields.
Is CANNA suitable for beginners?
Yes, they offer simple feeding schedules and clearly structured nutrient lines, making it suitable for beginners and experienced growers alike.
Shipping & Delivery


DELIVERY TIMEFRAME
We aim to process and dispatch all orders within 2 working days of being placed. Wherever possible, parcels are sent on a next working day service to ensure you receive them quickly and reliably.
When your order is dispatched, you will receive a confirmation email with tracking information so you can closely monitor your delivery every step of the way.
Please Note: Delivery times may slightly vary during busy periods, or due to courier service disruptions. Rest assured, we always do our best to get your order to you promptly.
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