Cal/Mag Pro Series Hydroponic Plant Nutrients - Coco Ready

Our review of Cal/Mag Pro Series finds it best suited for growers who want a straightforward, naturally derived calcium and magnesium supplement that works well in coco coir and other media. The single biggest reason to buy is its focused 4:1 calcium to magnesium ratio, which addresses common deficiencies in coco and improves uptake without introducing industrial byproducts. For hobbyists and small commercial growers seeking a clean, easy-to-use powdered nutrient to strengthen stems and leaves, this formula delivers reliable, plant-ready nutrition.

Key Features

• Pure & Natural Ingredients: Formulated from 100% naturally sourced components so plants get essential micro and macro elements without industrial byproducts.
• Optimal 4:1 Ca:Mg Ratio: The specific calcium to magnesium balance helps prevent deficiency symptoms commonly seen in coco coir and supports even nutrient uptake.
• Coco Pre-Treatment: Can be used to flush excess sodium and chloride from coco coir before planting to create a cleaner starting medium.
• Balanced Growth & Uptake: Designed to promote strong stems and healthy leaves while improving the plant's ability to absorb other nutrients.
• Grower-Designed Quality: Developed by growers in California and backed by customer support through the Grow Strong Industries family of brands.
• Easy-to-Use System: Works as a supplement within a feeding schedule that suits both beginners and experienced growers from seedling to harvest.

Who It's For

Cal/Mag Pro Series is aimed at gardeners using coco coir or soil who need to correct or prevent calcium and magnesium deficiencies. It is particularly useful for tomato, vegetable, and flowering crops that benefit from stronger stems and improved nutrient uptake. The natural sourcing will appeal to growers prioritizing cleaner inputs.

It may be less suitable for those who require a complete all-in-one fertilizer or who expect an ultra-fine, instantly dissolving powder; several users reported varied powder consistency and some clumping that requires breaking up before use. Users who need a liquid concentrate or exact lab-grade granulation might look elsewhere.

Pros & Cons

Pros

• Natural, plant-derived ingredients reduce exposure to industrial byproducts while supplying essential elements.
• The 4:1 calcium to magnesium ratio is tailored for coco coir and helps prevent common nutrient deficiencies.
• Useful as a coco pre-treatment to flush unwanted salts from growing media before planting.
• Backed by grower experience and customer support from a recognized industry brand family.

Cons

• Powder consistency receives mixed feedback; some batches can be clumpy and require effort to dissolve fully.
• Not a standalone complete fertilizer; must be used as a supplement within a feeding program.

Specifications

Product Type	Calcium and Magnesium Supplement
Form	Powdered nutrient
Primary Use	Soil, hydroponic, and coco coir
Calcium:Magnesium Ratio	4:1
Net Weight	120oz
Brand Family	Grow Strong Industries (Lotus Nutrients)

Our Verdict

Cal/Mag Pro Series is a practical, value-oriented supplement for growers who need a clean, effective calcium and magnesium boost, especially in coco coir. Its naturally sourced formula and targeted 4:1 ratio make it a sensible addition to feeding schedules, though users should be prepared to manage occasional clumping and combine it with a complete nutrient program for best results.

Frequently Asked Questions

Can this be used in coco coir?
Yes. It is specifically formulated with an ideal 4:1 calcium to magnesium ratio and can also be used to pre-treat coco to flush excess sodium and chloride.

Is this a complete fertilizer?
No. This is a calcium and magnesium supplement designed to be used alongside a complete nutrient regimen rather than as a sole source of plant nutrition.

How is the powder to mix?
Most users find it effective but note the powder can be clumpy; breaking up clumps and ensuring full dissolution before adding to the reservoir improves results.