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Compatible with any nutrient system: 100% compatible with other nutrient systems, and can help make other minerals more bio-available. Apply with every watering for the full benefit.

Suitable for hydroponics, soil, and container gardens: Nutrient systems and supplements are commonly used as hydroponic supplies and are a good solution for soil and container gardens, ensuring strong and healthy plants and yields.
Corrects common plant deficiencies: sometimes an unhealthy plant may be suffering from a nutrient deficiency or even too much of one nutrient. Our well-balanced formula is designed to specifically address any plant deficiencies that may be present. Our calmag & iron supplement effectively corrects and remedies these micronutrient plant deficiencies.

While R. O. While it performs well, essential nutrients become locked up in its fibers. Most calmag blends you will find are created by blending Calcium Chloride, which is less friendly for plants and hydro systems.
O. Water offers consumers unparalleled purity, it strips minerals necessary for plant growth - ENVY's CalMag+ Fe replenishes water stripped of minerals. Prevents blossom end rot - our calmag+ fe provides tomatoes, Peppers and other hydroponically grown crops an ample concentration of highly-absorbable Calcium, preventing Calcium Deficiency which causes leaf yellowing & blossom end rot in Tomatoes and Peppers. Formulated to replace minerals depleted by reverse osmosis water applications.

Even with the right amount of N-P-K, phosphorous and potassium however, growth and yield. Formulated for use in all soil, container, coco and hydro growing. We all know plants need adequate primary nutrients nitrogen, a small deficiency in either secondary or micro-nutrients can severely limit plant health, they also need the right amount of both secondary nutrients and trace elements or micro-nutrients.


High-grade, concentrated formula.



Potent plants: establish nutrient-rich soil for optimal plant growth and production with the help of our unique indoor plant fertilizer formula complete with calcium; Enjoy consistently high yields and faster growth.
Precisely balanced formula: Our high-nitrate nitrogen fertilizer is packed with potassium, calcium, and magnesium for improved plant quality and color. Dakine difference: dakine 420 is guided by real, bona-fide “Mad Scientists” with over a half-century of experience working in state-of-the-art indoor growing facilities; Discover the difference today.

1. Bloom City
#ad
Bloom City Professional Grade Ultra Pure Cal-Mag Growing Fertilizer, Quart 32 oz
#adBloom City #ad - Bioactivated formula for optimal nutrient uptake: Calcium and magnesium, Micro-chelated with fulvic acid; if you google it you’ll see why that’s good. Contains more micronutrients than any other brand: Iron Fe, Copper Cu, Manganese Mn, Zinc Zn, Boron B, Molybdenum Mo, Sulfur S.Compatible with any nutrient system: 100% compatible with other nutrient systems, and can help make other minerals more bio-available. Apply with every watering for the full benefit.
More information #ad
Prevents common growth deficiencies: Apply Cal-Mag in every stage of growth for strong stalk and leaf health. We choose only the highest quality ingredient sources and manufacturing methods to create the world’s best craft growing nutrient systems. Contains no harmful edta: unlike other brands, bloom city uses organic chelates and never uses chemicals like EDTA, Healthier for your garden and healtier for the planet.Brand | Bloom City #ad |
Manufacturer | Bloom City #ad |
Part Number | calmag-32 |
More information #ad
2. Humboldts Secret
#ad
Humboldts Secret Calcium, Magnesium and Iron Supplement – Hydroponic Supplies – Liquid Nutrient Fertilizer – Supports Vegetative and Flowering Stage – 1 Quart
#adHumboldts Secret #ad - Nutrient uptake and absorption: this formulae efficiently supports nutrient uptake and absorption by addressing any plant deficiencies in the first place, thus successfully supporting the vegetative and flowering stage of your plants. Source of calcium magnesium & chelated iron: Many varieties of flowering plants require higher levels of these micronutrients.Suitable for hydroponics, soil, and container gardens: Nutrient systems and supplements are commonly used as hydroponic supplies and are a good solution for soil and container gardens, ensuring strong and healthy plants and yields.
More information #ad
Optimal for coco coir medium and reverse osmosis water: Our supplemental CalMag & Iron by Humboldts Secret is highly recommended for plants growing in coco substrate or reverse osmosis water, as the absorption process becomes magnified. Corrects common plant deficiencies: sometimes an unhealthy plant may be suffering from a nutrient deficiency or even too much of one nutrient. Our well-balanced formula is designed to specifically address any plant deficiencies that may be present. Our calmag & iron supplement effectively corrects and remedies these micronutrient plant deficiencies.
Brand | Humboldts Secret #ad |
Manufacturer | Humboldts Secret #ad |
More information #ad
3. ENVY
#ad
ENVY CalMag+ Fe 4-0-0 Professional Grade Calcium, Magnesium and Iron Liquid Plant Food | Superior Calcium Source No Calcium Chloride 8 oz
#adENVY #ad - Corrects coir nutrient lock up - coco-coir is a popular growing media for hobbyist and professional gardeners alike. Better together - our calmag+ fe performs excellently with all hydroponic, soil and coir nutrient lines as a supplementary Calcium, Magnesium and Iron source - however; it performs best when combined with ENVY's A & B base nutrients and Bloom Trigger concentrate.While R. O. While it performs well, essential nutrients become locked up in its fibers. Most calmag blends you will find are created by blending Calcium Chloride, which is less friendly for plants and hydro systems.
More information #ad
Our concentrated CalMag+ replenishes nutrients lost to lock-up. Superior cal-mag - envy's calmag+ is derived from a superior source of Ca, Calcium Nitrate. Perfect for r. O. Water offers consumers unparalleled purity, it strips minerals necessary for plant growth - ENVY's CalMag+ Fe replenishes water stripped of minerals. Prevents blossom end rot - our calmag+ fe provides tomatoes, Peppers and other hydroponically grown crops an ample concentration of highly-absorbable Calcium, preventing Calcium Deficiency which causes leaf yellowing & blossom end rot in Tomatoes and Peppers. Formulated to replace minerals depleted by reverse osmosis water applications.
Brand | ENVY #ad |
Manufacturer | National Liquid Fertilizer #ad |
More information #ad
4. GS Plant Foods
#ad
Magnesium, Iron and Sulfur Supplement, N-P-K of 2-0-0, Corrects Secondary Nutrient & Trace Element Deficiencies, GS Plant Foods Cal-Mag Extreme Liquid 1 Gallon Fertilizer with Calcium
#adGS Plant Foods #ad - Easy-to use just mix with water. Beneficial to plants throughout all growth cycles and easily mixes with water to use during irrigation or as a foliar spray. Gs plant foods’ cal-mag extreme solves the problem.Even with the right amount of N-P-K, phosphorous and potassium however, growth and yield. Formulated for use in all soil, container, coco and hydro growing. We all know plants need adequate primary nutrients nitrogen, a small deficiency in either secondary or micro-nutrients can severely limit plant health, they also need the right amount of both secondary nutrients and trace elements or micro-nutrients.
More information #ad
It contains calcium, sulfur, zinc, manganese, Magnesium, Iron, Boron & Molybdenum all in an immediately plant available form with natural chelates for fast plant absorption.Brand | GS Plant Foods #ad |
Part Number | CMextGal |
More information #ad
5. Dutch Science Nutrients
#ad
Calcium & Magnesium Supplement Fertilizer for The Prevention & Repair of Common Plant Nutrient Deficiencies 1.1 lb, Dutch Science Nutrients Cal-Mag Plus Humates
#adDutch Science Nutrients #ad - Contains organic humates - they help your garden retain more water, increase root and plant strength, and help your plants absorb more nutrients. Creates 160 gallons of nutrient mixture. This helps keep your nutrients fresh and effective.More information #ad
Easily mix in the nutrients you need with fresh water, store the rest. Repairs and prevents calcium and magnesium deficiencies, speeds up plant growth, and produces better yields. Our nutrients can be used in soil, coco, or hydroponic home grow systems.Brand | Dutch Science Nutrients #ad |
Manufacturer | Dutch Science Nutrients #ad |
More information #ad
6. Blue Planet Nutrients
#ad
CalMag + Iron Liquid Plant Supplement Quart 32 oz Blue Planet Nutrients | Calcium Magnesium Iron for All Plants & Gardens | Prevents & Corrects Blossom End Rot | Vegetables Fruits Flowers Herbs
#adBlue Planet Nutrients #ad - Designed for use in all hydroponic systems, perlite, aeroponics, all soil-less mediums such as vermiculite, coco-coir, and in soil. Calmag with iron supplement is used for plants that require elevated levels of calcium and magnesium to reach their fullest potential and is excellent at preventing and correcting blossom end rot.High-grade, concentrated formula.
More information #ad
Blue planet nutrients uses only the highest quality ingredients in our hand-crafted nutrient formulas. Proven results across the internet! See why everyone is raving about Blue Planet Nutrients! This product helps strengthen cell walls resulting in stronger plant structures and greater overall health.Brand | Blue Planet Nutrients #ad |
Manufacturer | Blue Planet Nutrients #ad |
Height | 7.5 Inches |
Length | 5.25 Inches |
Width | 2.4 Inches |
Part Number | 4336441504 |
More information #ad
7. RAW ELEMENTS
#ad
2-Ounce, 2 Ounce, NPK Industries 717861 Raw Calcium/Magnesium Fertilizers
#adRAW ELEMENTS #ad - Raw calcium/mag contains 15% calcium and 3% magnesium. Brand: npK Industries. Item weight: 0125 lbs. Raw calcium/mag is a stand alone Calcium/Mag supplement.More information #ad
Brand | RAW ELEMENTS #ad |
Manufacturer | NPK Industries #ad |
Height | 6.5 Inches |
Length | 4.25 Inches |
Weight | 0.13 Pounds |
Width | 1 Inches |
Part Number | 280 |
Model | 717861 |
More information #ad
8. NPK Industries
#ad
NPK Industries 717863 Raw Calcium/Magnesium Fertilizers, 8 Ounce, 8-Ounce
#adNPK Industries #ad - Raw calcium/mag is a Stand Alone Calcium/Mag Supplement. Raw calcium/mag contains 15% Calcium And 3% Magnesium. No assembly Required.More information #ad
Raw calcium/mag has optimized the ratio of each element in a water Soluble Formulation Of Calcium Nitrate And Magnesium Sulfate So That It Doesn’T Leave The Media Salty.Brand | NPK Industries #ad |
Manufacturer | NPK Industries #ad |
Height | 8 Inches |
Length | 3.7 Inches |
Weight | 0.5 Pounds |
Width | 1.5 Inches |
Part Number | 281 |
Model | 717863 |
More information #ad
9. DaKine 420
#ad
Indoor Plant Fertilizer w/ Calcium & Magnesium- Nutrient Powder Tree Food, Dakine’s 420 Indoor Plant Food CalMag 1000g
#adDaKine 420 #ad - Super clean: our 100% water-soluble plant food is crystal clear, won’t clog your lines, plug your tips, or leave residue in your reservoir, meaning you spend less time cleaning. Powerful plant fertilizer: a delicious 12-2-12 product containing 6% calcium and 3% magnesium for consistently beneficial results when cultivating buds.Potent plants: establish nutrient-rich soil for optimal plant growth and production with the help of our unique indoor plant fertilizer formula complete with calcium; Enjoy consistently high yields and faster growth.
More information #ad
Precisely balanced formula: Our high-nitrate nitrogen fertilizer is packed with potassium, calcium, and magnesium for improved plant quality and color. Dakine difference: dakine 420 is guided by real, bona-fide “Mad Scientists” with over a half-century of experience working in state-of-the-art indoor growing facilities; Discover the difference today.
Brand | DaKine 420 #ad |
Manufacturer | DaKine 420, LLC. #ad |
Height | 3.5 Inches |
Length | 6.5 Inches |
Weight | 1000 Grams |
Width | 6.5 Inches |
Part Number | 728028467222 |
More information #ad
10. Technaflora
#ad
Technaflora TFMC4L Magnesium Calcium Blend Liquid MagiCal Fertilizer for Flowers, Vegetables, Trees, 4 Liters, Lawns, Gardens
#adTechnaflora #ad - Accelerates protein syntheses, Maintains high starch content in crops. Improves the nutritional quality of plants. Contains magnesium, Iron and calcium to have healthier plant growth.More information #ad
Improves the density of fruit and the production of essential oils. Creates lush and greener foliage and Maintains a healthy root system.Brand | Technaflora #ad |
Manufacturer | Technaflora #ad |
Height | 11.3 Inches |
Length | 6 Inches |
Weight | 10.45 Pounds |
Width | 6 Inches |
Part Number | 716455 |
Model | TFMC4L |
More information #ad