Newmarket, Ontario (Head Office)
1175 Stellar Drive, Unit #5
Newmarket, ON L3Y 7B8
- Mon10:00am–6:00pm
- Tue10:00am–6:00pm
- Wed10:00am–6:00pm
- Thu10:00am–6:00pm
- Fri10:00am–6:00pm
- Sat10:00am–4:00pm
- SunClosed
$0.00 CAD
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Advanced Nutrients Sensi Cal-Mag Xtra® is a liquid cal-mag plant nutrient additive that provides supplemental calcium and magnesium for growers running a complete base fertilizer program in vegetative and bloom.
This formula features chelated calcium and chelated magnesium, plus added chelated micronutrients including iron, manganese, and zinc. With an NPK of 4-0-0, it’s typically used to complement a full nutrient schedule when extra calcium, magnesium, and supporting micros are desired.
Kelp extract is also included as part of the ingredient profile, making this more than a basic calcium-magnesium product for growers who prefer a cal-mag additive that includes marine-plant inputs in the same bottle.
For system compatibility, this cal-mag additive is commonly used in hydroponics and coco coir, and it can be incorporated into routine feeding across a wide range of indoor and outdoor garden setups.
Step-by-step mixing and feeding instructions for Advanced Nutrients Sensi Cal-Mag Xtra - 500 ML.
Fill your reservoir or watering container with clean, room-temperature water first. Shake the bottle of Advanced Nutrients Sensi Cal-Mag Xtra - 500 ML well before every use. Using the feeding schedule below, measure the recommended dose and add it directly to the water while stirring. Allow the solution to mix fully before adding any other fertilizers, additives, or supplements.
Always add nutrients to water — not the other way around. Mix thoroughly between products to ensure an even, stable nutrient solution.
Vegetative stage — Sensi Cal-Mag Xtra
Flowering stage — Sensi Cal-Mag Xtra
Warning – Important Safety Information
This product may cause mild skin irritation and eye irritation. Avoid unnecessary contact with skin, eyes, and clothing. Use only as directed.
General safety precautions
Read and follow all instructions on the product label and any accompanying documentation before use. Keep out of reach of children and pets. Do not ingest. Avoid breathing vapours, mist, or dust that may be generated during handling or use.
Wear appropriate personal protective equipment (PPE), such as protective gloves, long sleeves, long pants and closed-toe footwear. When there is a risk of splashing or airborne particles, use safety glasses or other suitable eye and face protection.
First aid – skin contact
IF ON SKIN OR HAIR: Remove contaminated clothing immediately. Rinse skin with clean water for several minutes, then wash with mild soap and water. If irritation or redness develops and persists, seek medical attention. Wash contaminated clothing before reuse.
First aid – eye contact
IF IN EYES: Rinse cautiously with clean water for several minutes, keeping eyelids open. Remove contact lenses if present and easy to do. Continue rinsing. If irritation persists, obtain medical advice.
First aid – ingestion and inhalation
IF SWALLOWED: Rinse mouth thoroughly with water. Do not induce vomiting unless instructed by a medical professional. Seek medical attention if you feel unwell.
IF INHALED: Move the person to fresh air and keep them comfortable for breathing. If coughing, breathing difficulty, dizziness or other symptoms occur, seek medical assistance.
Storage and handling
Store this product in its original closed container, in a cool, dry and well-ventilated area. Protect from extreme temperatures and direct sunlight. Keep container tightly sealed when not in use.
Avoid release to drains, natural waterways or outdoor soil. Dispose of unused product and empty containers in accordance with local regulations and the directions on the label.
Important: If medical advice is needed, keep the product label or container available. Always follow the specific instructions and safety recommendations provided by the manufacturer. This safety notice is intended as general guidance and does not replace official label directions or documentation.
| Nitrate Nitrogen (N) | 4.0% |
|---|---|
| Calcium (Ca) | 3.2% |
| Total Magnesium (Mg) | 1.1% |
| Water Soluble Magnesium (Mg) | 1.0% |
| Chelated Iron (Fe) | 0.09% |
| Chelated Manganese (Mn) | 0.05% |
| Chelated Zinc (Zn) | 0.05% |
| Ascophyllum Nodosum | 0.1% |
Ascophyllum nodosum supports stronger root growth, improves stress resistance, enhances nutrient uptake, and helps plants maintain balanced, steady development throughout their entire growth cycle.
Calcium is important because it builds and stabilizes plant cells as they form, acting as the structural support that keeps new growth strong and functional. Unlike other nutrients that drive color or speed of growth, calcium’s role is unique because it controls cell wall strength and membrane stability, making it essential for healthy roots, shoots, and long-term plant resilience rather than quick visual results.
Calcium nitrate is important because it supplies calcium in a fast, highly available form that supports strong new growth and healthy root tips, while also providing nitrate nitrogen for steady, usable growth energy. It’s unique because it delivers calcium together with nitrate nitrogen, making it especially effective during rapid growth phases when plants need both structure-building calcium and immediately available nitrogen at the same time.
Chelated iron is important because it keeps iron usable for plants even when growing conditions would normally lock iron out, helping prevent the classic yellow-new-leaf symptom caused by low chlorophyll production. It is unique from other iron sources because the chelation protects iron from becoming insoluble, making it a more reliable way to correct iron-related chlorosis when regular iron can fail.
Chelated manganese is important because it keeps manganese available for photosynthesis and enzyme activity even when pH or water chemistry would normally lock it out, and it’s unique from similar micronutrients because it strongly supports the plant’s energy-processing systems that drive healthy, resilient new growth.
Chelated zinc is important because it keeps zinc available for uptake even when pH or root-zone conditions would normally lock zinc out, helping plants form normal-sized, healthy new growth—something that makes zinc uniquely different from many other nutrients that mainly affect older leaves or simple leaf color changes.
Nitrate Nitrogen provides a stable, easy-to-absorb form of nitrogen that supports steady growth, strong foliage, and reliable plant development without sudden nutrient swings.
Total magnesium is important because magnesium powers chlorophyll and energy use, helping plants stay green, turn light into growth, and use other nutrients efficiently—and it’s unique because its problems often come from nutrient balance and uptake competition, not just a simple shortage.
Water soluble magnesium is important because it quickly restores the plant’s ability to make chlorophyll and produce energy, which helps stop interveinal yellowing on older leaves and improves overall nutrient use; it’s unique because it becomes available immediately in water, making it faster and more predictable than slower magnesium sources.
Iron EDTA keeps iron dissolved and available long enough for roots to absorb it, which is why it can quickly improve new growth color when iron is tied up in the root zone. It’s unique because the EDTA chelate balances stability and accessibility, making iron more reliably usable in mildly acidic to near-neutral conditions compared to many non-chelated iron forms.
Magnesium nitrate supplies fast-available magnesium for chlorophyll and photosynthesis while also adding nitrate nitrogen that can speed up greening and growth. It’s unique because it can correct magnesium-related yellowing quickly but also changes growth momentum, so it’s most valuable when magnesium is truly limiting and the plant can safely use extra nitrate.
Manganese EDTA is unique because the EDTA chelate keeps manganese stable and more available during delivery, helping plants absorb it more reliably when manganese would otherwise lock up. This matters because manganese drives key enzyme functions tied to photosynthesis and healthy new growth, so consistent availability can prevent pale, chlorotic young leaves and stalled vigor.
Seaweed is mainly a plant booster because it supports roots, stress tolerance, and nutrient efficiency more than it supplies full nutrition. It’s unique because ocean-derived compounds help the root zone and plant growth signals in a gentle way, so plants often recover faster and grow more steadily when the basics are already covered.
Zinc EDTA is important because it keeps zinc available in the root zone when pH or water chemistry would normally tie zinc up, helping new growth develop normally before deficiency symptoms get worse. It’s unique from other zinc forms because the EDTA chelate shields zinc in solution, making delivery more consistent when conditions are not ideal.

Best Cal-Mag you can give your plants.
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