Canna CalMag Agent

In stock online
Standard Delivery £6.95*
Free Delivery - orders +£65 Free Delivery - orders +£65
Plain Packaging Used Plain Packaging Used
Click and Collect Click and Collect
Product Name Qty Price
Canna CalMag Agent - 1L
Canna CalMag Agent - 5L
Canna CalMag Agent - 10L


If you live in a soft water area, then you should be using the newly released CalMag Agent by Canna. Developed due to popular demand, CalMag Agent helps to harden soft water, by introducing additional levels of Calcium and Magnesium to your nutrient solution.

Soft water, generally speaking, has an EC reading of approximately 0.2, the optimum level for strong and healthy plant growth is between 0.4 to 0.7. By using Canna CalMag Agent, it will not only add much needed calcium and magnesium, it will also raise the EC to the required level.

By using Canna CalMag Agent, along with increasing the EC, the plants nutrient absorption will be improved and deficiencies will decrease, resulting in stronger, healthier plants with enhanced fruit and flower production.

Canna CalMag Agent can also be used in hard water areas with an EC reading of greater than 0.8, but Canna advise that a Reverse Osmosis (RO) filter should be used to initially reduce the EC, then CalMag Agent is added until the EC reaches the required 0.4.-0.7.


  • Helps to stabilise EC levels in soft water regions
  • Provides additional levels of Calcium & Magnesium
  • Promotes healthier and stronger plant growth
  • Improves fruit and flower production
  • Can be used in hard water regions when using Reverse Osmosis (RO)

Canna CalMag Agent is also a highly concentrated formula, so just 1ml per litre of water is all that’s needed to make a difference to the health, growth and flower production of your plants.


Read on our blog: The Importance Of Using CalMag Supplements

Delivery & Returns
Free Delivery
We are pleased to offer free standard shipping to UK Mainland on all orders over £65.00 *Heavy item surcharges are still applicable.
Next Day Delivery
In a hurry for your order? Order before 1 pm Mon - Thurs for next working day delivery *subject to stock availability T&C's apply.
Different delivery address?
Do your goods need shipping to an alternative address? If so, paying by bank transfer gives you the freedom to have them delivered to anywhere in the UK.
Free Returns
Faulty or damaged item? No problem, contact us on 0800 038 7100 or email customer service and we can arrange a free collection.
Plain Packaging
All parcels, no matter how big or small, are dispatched in plain packaging using black wrap that's secured using 'fragile' tape.
How to Pay
Credit / Debit Cards
We accept all major credit and debit cards. Please note: When paying by credit card we can only ship to the card statement address.
Simply select this option at checkout if you prefer to pay through PayPal. Please note: When paying by PayPal, we can only ship items to the account owners confirmed address.
Bank Transfer
Select the option for Bank Transfer at checkout if you wish to receive your item anywhere within the UK. Please use your order number as payment reference.
Split your purchase into manageable payments. Buy now and pay in 30 days or in three interest-free instalments with Klarna.
Click & Collect
Collect your online orders in as little as under an hour*! Simply pay online, choose your store & collect for free! Available from Manchester & Huddersfield (*subject to stock availability).
Brand Canna
You must be logged in to ask questions.