Advanced Nutrients Sensi Cal-Mag Xtra — Liquid Calcium & Magnesium Supplement for Hydroponic Growing
Best for: Growers running coco, RO water systems, or any hydroponic setup where calcium and magnesium deficiencies are costing you green leaves
Our thoughts
This is the step up from generic cal-mag. The chelated iron ratios and amino acid package actually make a difference—leaves that were turning yellow come right again, usually within 48 hours. If you're serious about your setup and not just looking for the cheapest bottle, this one's worth the outlay. Particularly solid if you're growing in coco or running reverse osmosis water.
Sensi Cal-Mag Xtra is a liquid calcium and magnesium supplement designed to prevent and correct secondary nutrient deficiencies in hydroponic, coco, and soil-based growing systems. Unlike basic cal-mag products, this formulation includes enhanced chelated iron in precise ratios, plus 20 L-form amino acids that boost nutrient uptake and plant vigour across the board. It's built to integrate seamlessly with Advanced Nutrients' range, but works just as well alongside any other base nutrient system.
How it compares
The cal-mag supplement market splits into three tiers. Sensi Cal-Mag Xtra sits firmly in the premium specialist category.
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Budget alternatives (CALiMAGic, Procal) — basic calcium and magnesium, reliable but nothing extra. Good if your plants rarely show deficiency symptoms.
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Mid-range products (Botanicare Cal-Mag Plus, Humboldts Secret) — broader system compatibility, slightly better nutrient profiles, coco-specific formulations.
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Sensi Cal-Mag Xtra — enhanced iron chelation ratios, amino acid package, and Advanced Nutrients' research backing. Measurably faster deficiency correction and stronger preventative action.
In plain terms: you're paying more because the formula actually works faster and more thoroughly than commodity alternatives.
Usage guidance
Sensi Cal-Mag Xtra works across all hydroponic and growing media systems. How you use it depends on your setup:
As part of your regular feeding program
Add 2 mL per litre of water once a week, alongside your base nutrients. This is preventative—stops deficiencies before they start. Works brilliantly in coco coir, where calcium and magnesium naturally bind and become unavailable to plants.
Correcting an active deficiency
If your leaves are already yellowing or showing tip burn, use 2 mL per litre and repeat after one week if symptoms persist. Most growers see improvement within 48 hours.
Hydroponic systems
Compatible with all common setups: drip irrigation, flood and drain, NFT, deep water culture, aeroponics. Mix into your reservoir as part of your regular feeding schedule.
Foliar application
Can be sprayed directly onto leaf material at 2 mL per litre. Repeat weekly if addressing deficiency symptoms. Works fastest this way if plants are severely yellowed.
Reverse osmosis water
If you're running RO water (which has zero mineral content), this becomes part of your baseline nutrition, not just an optional extra. Essential for preventing secondary deficiencies.
Technical specifications
- Form: Liquid concentrate
- NPK Ratio: 4-0-0
- Active ingredients: Calcium nitrate, magnesium nitrate, chelated iron (EDTA), manganese EDTA, zinc EDTA
- Amino acids: 20 L-form amino acids included
- Application rate: 2 mL per litre (weekly)
- Available sizes: 1L, 4L, and 23L bottles
- System compatibility: All hydroponic systems, coco, soil, and soil-less media
- Base nutrient compatibility: pH Perfect Advanced Nutrients range, all other base nutrients and competitors' supplements
- Guarantee: 100% Money-Back Grower Guarantee (6 months, unused portion with receipt)
Who this is for
- Growers running coco coir systems who need reliable calcium and magnesium supplementation
- Anyone using reverse osmosis water or soft water that lacks natural minerals
- Experienced hydroponic growers who want faster deficiency correction and prevention
- Commercial or multi-room operations where plant health directly affects yield
- Anyone already using Advanced Nutrients' Micro, Grow, Bloom series looking to complete their nutrient toolkit
- Growers dealing with repeated yellowing, tip burn, or stunted growth caused by secondary nutrient lockout
Less suited to beginners on a tight budget who'd benefit more from a basic cal-mag product first, or growers in hard-water areas where calcium and magnesium are already abundant in their tap water.
Our take
If you're serious about your hydroponic setup and sick of guessing why your leaves keep turning yellow, this supplement does what the premium alternatives do—corrects deficiency symptoms fast and keeps them from coming back. The amino acid package and iron chelation ratios aren't marketing fluff; they genuinely speed up nutrient uptake and plant recovery.
Worth picking up if you're running coco, RO water, or a locked-in hydroponic system. Does exactly what it should, day in, day out, and the results show within a week. Good time to grab a bottle while clearance stock lasts.
