Green Planet Pro Cal is a calcium, magnesium and iron supplement designed for use alongside your regular plant nutrient program. This Pro Cal additive supplies key minerals involved in plant formation, chlorophyll production and normal nutrient transport.
It is particularly useful for growers using coco coir, hydroponic substrates, reverse osmosis water or rainwater, where additional calcium and magnesium may be required. ProCal can be used throughout the vegetative and flowering stages and is available in 1L and 5L sizes.
Key benefits
- Provides a readily available source of calcium, magnesium and iron.
- Supports healthy plant formation, cell division and chlorophyll production.
- Helps maintain balanced calcium and magnesium levels in nutrient programs.
- Supports substrate buffering and cation exchange in coco coir.
- Suitable for use with hydroponic, coco and soil-based growing systems.
- Can be added to feed programs using low-mineral RO or rainwater.
Best suited to
Green Planet Pro Cal is well suited to growers who need a practical Cal-Mag supplement for:
- Coco coir and other hydroponic substrates.
- Hydroponic nutrient programs.
- Reverse osmosis or rainwater-based feeding.
- Vegetative and flowering plants.
- Substrate buffering or re-buffering.
- Plant nutrition programs requiring additional calcium, magnesium and iron.
How to use it
For general use, add Green Planet Pro Cal at 1.25 mL per litre of water with your nutrient program. Use throughout the grow cycle until one week before harvest.
Mix Pro Cal into your prepared nutrient solution and agitate thoroughly to distribute it evenly. Check the final EC and pH of the solution before feeding, particularly when combining it with other nutrients or additives.
When re-buffering coco coir, the manufacturer recommends using a one-third-strength nutrient solution with Pro Cal at 2 mL per litre.
Always follow the Green Planet feeding calculator or nutrient program for guidance suited to your plants and growing system.
Choosing the right option
-
1L: A practical choice for smaller gardens, occasional supplementation or growers trying Pro Cal for the first time.
-
5L: Better suited to larger reservoirs, multiple plants or growers who use Cal-Mag regularly throughout their feeding program.
Check before buying
- Confirm whether your existing base nutrients already contain calcium, magnesium or iron.
- Consider your water source, as RO and rainwater generally contain fewer dissolved minerals than tap water.
- Select the bottle size that matches your reservoir volume and expected frequency of use.
- Use Pro Cal as a nutrient additive rather than a complete base nutrient.
- Follow your chosen nutrient schedule and monitor the final EC and pH after mixing.
FAQs
What does Cal-Mag do for plants?
Calcium supports plant formation, healthy cell division and enzyme activity. Magnesium is involved in chlorophyll production and nutrient transport, while iron also contributes to chlorophyll production and normal enzyme function.
Can Green Planet Pro Cal be used in coco coir?
Yes. Pro Cal is recommended for coco coir and can also be used when buffering or re-buffering coco substrate.
Can I use Pro Cal with hydroponic nutrients?
Yes. It is designed to be added alongside a nutrient program and is suitable for hydroponic substrates. Mix thoroughly and check the final EC and pH before feeding.
Is Pro Cal useful with RO or rainwater?
Yes. The manufacturer specifically recommends adding Pro Cal to feed programs that use reverse osmosis water or rainwater.
Choose Green Planet Pro Cal when your grow program needs a straightforward source of calcium, magnesium and iron for coco, hydroponic or soil-based plants.
Unconditional Satisfaction Guarantee
