★★★★★
Fixed my leaf issues within two weeks
I started using this calmag after noticing yellowing and weak growth within about 2 weeks it had improved leaved firmed up and colour improved again
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Cal-Mag Hydroponic Nutrients Fertiliser
Price range: $36.00 through $46.70
High-strength CAL-MAG for fast-growing, heavy-feeding plants.
✅ Chelated Calcium & Magnesium for rapid absorption
✅ Helps prevent blossom end rot, tip burn & stunted growth
✅ Double the strength of standard Cal-Mag formulas
✅ Used by commercial hydroponic growers
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Boost Plant Growth
CAL – MAG
NPK 4-0-0
Our Complete Grow CAL-MAG is made from a special blend of chelates and mineral nutrients for effective and fast absorption by plants.
Analysis
- 🧪 Calcium – 6%
- 🧪 Magnesium – 2%
- 🧪 Iron EDTA – 0.1%
- 🌿 Plus all trace minerals
Complete Grow Cal-Mag is a concentrated Chelated Calcium and Magnesium solution which improves the overall health of the plants. It assists fast-growing and heavy-feeding plants to uptake the required nutrients. It also helps prevent blossom end rot, tip burn, poor setting, and stunted growth.
Double the strength of other Cal-Mag products. Made and used by commercial hydroponic farmers using high-grade chelated fertiliser.
Direction
Apply 0.5 to 1ml per litre of water. Can be used in both grow and flower stages.
Reviews
5.0
★★★★★
Based on 3 reviews
★★★★★
Fixed my leaf issues within two weeks
I started using this calmag after noticing yellowing and weak growth within about 2 weeks it had improved leaved firmed up and colour improved again
★★★★★
definitely helped
Wasnt sure if i needed this, but definitely helped my plant. Growth looks healthier now
★★★★★
Did exactly what I needed it to
Started using this after my plants started showing blossom end rot
in a couple of weeks the new fruit came through clean and haven't had it since
Cal-Mag Hydroponic Nutrients Fertiliser
Double-strength Cal-Mag fertiliser made with chelated Calcium, Magnesium, and Iron for fast-growing plants. Prevents common deficiencies like blossom end rot and tip burn. Ideal for hydroponics or soil. NPK 4‑0‑0. Trusted by commercial growers. Free shipping Australia-wide.
High-strength Cal-Mag formula for fast-growing plants
✅ Chelated Calcium & Magnesium for rapid absorption
✅ Prevents blossom end rot, tip burn & stunted growth
✅ Twice the strength of standard Cal-Mag formulas
✅ Suitable for hydroponics & soil-based systems
✅ Made in Australia – trusted by commercial growers
✅ Chelated Calcium & Magnesium for rapid absorption
✅ Prevents blossom end rot, tip burn & stunted growth
✅ Twice the strength of standard Cal-Mag formulas
✅ Suitable for hydroponics & soil-based systems
✅ Made in Australia – trusted by commercial growers
NPK Ratio — Cal-Mag (Hydroponic)
-
N
4
-
P
0
-
K
0
-
Ca
6%
-
Mg
2%
-
Fe
0.1%
What Cal-Mag (NPK 4-0-0) Means
Chelated Calcium and Magnesium to strengthen new growth, deepen green colour and stabilise nutrient uptake in hydro, coco and soil. Double strength for fast correction and steady support.
- Stronger structure: Calcium reinforces cell walls and root tips for firm, resilient growth.
- Greener leaves: Magnesium drives chlorophyll production for rich colour and efficient photosynthesis.
- Prevents issues: Helps avoid blossom-end rot, tip burn, poor setting and stalled growth in fast-growing, heavy-feeding plants.
Read More
Cal-Mag supplies essential Calcium and Magnesium in forms plants can absorb quickly. Calcium supports strong meristems, roots and overall firmness, while Magnesium sits at the core of chlorophyll to power energy capture. Use whenever water is soft/RO, media is coco-based, light intensity is high, or feeds are heavy in potassium or ammonium which can compete with Ca/Mg.
- Add to water first, mix well, then add base nutrients and any boosters.
- Hydro/coco: use a steady low dose each feed; soil: light, regular doses during active growth.
- Look for pale older leaves (Mg) or brittle tips/poor fruit set (Ca) as signs to maintain Cal-Mag support.
Best For These Plants
Prevents Blossom End Rot & Tip Burn
Supports Strong Growth & Nutrient Uptake
How it Works
Mix 0.5–1ml per litre of water
Feed Your Plants
Watch Them Thrive
How Much to Mix
Cal-Mag — Mixing Calculator
Set your ml/L and litres — totals update automatically, with caps estimate.
Approx. 1 cap ≈ 15–20 ml.
Reviews From Our Gardener's
Reviews
5.0
★★★★★
Based on 3 reviews
★★★★★
Fixed my leaf issues within two weeks
I started using this calmag after noticing yellowing and weak growth within about 2 weeks it had improved leaved firmed up and colour improved again
★★★★★
definitely helped
Wasnt sure if i needed this, but definitely helped my plant. Growth looks healthier now
★★★★★
Did exactly what I needed it to
Started using this after my plants started showing blossom end rot
in a couple of weeks the new fruit came through clean and haven't had it since
Noticed healthier growth within a week. I use it in all my garden bed soils. very fast shipping have also used there all purpose liquid fertilizer combined with this have been seen great results
Ben R
Verified Buyer
This is a great fertiliser, have used for 2 weeks now and can see very good growth taking place .Will definitely get this again. I have very poor dirt where i live so this has helped my plants alot
Chloe M
Verified Buyer
FAQ
It supports cell strength, prevents deficiencies like blossom end rot or tip burn, and improves nutrient uptake in fast-growing crops.
This formula is double strength and uses chelated minerals for faster, more effective absorption. You need less to see better results.
Yes – it’s made for commercial hydroponics and works great in any system: NFT, DWC, coco, soil or drip setups.
Absolutely. It’s designed to be used in both veg and flower stages to support calcium and magnesium needs throughout the plant’s life cycle.
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