Plagron CalMag Pro for RO and Soft Water Grows

Build your nutrient water on the right foundation

A shortage of calcium and magnesium in reverse osmosis and soft water is one of the best-known problems in indoor growing, and one of the easiest to fix. Plagron CalMag Pro puts a balanced concentration of these minerals back into your water before anything else goes in, giving you a consistent starting point for the rest of the feed. Crucially it holds the optimal calcium to magnesium ratio, so the two elements do not compete with one another at the root.

Key Benefits

• Optimal Ca/Mg ratio prevents the two nutrients competing for uptake.
• Both elements in one product - many calcium and magnesium fertilisers cannot be mixed because of sulphates, CalMag Pro carries both in the correct proportion.
• Made for RO and soft water, the two supplies most likely to leave plants short.
• A stable base for nutrient water, so the base feed that follows behaves predictably.
• Simple to slot in ahead of any brand of base nutrient.

Pale New Growth on a Full-Strength Feed

Water with almost nothing in it looks clean on an EC meter but leaves plants short from the first feed. The symptoms are familiar: interveinal yellowing, rusty spots on older leaves, weak stems and slow growth, all of which are really poor nutrient uptake caused by a missing foundation rather than a weak base feed. Correcting calcium and magnesium first means the EC you dial in is doing the job you think it is.

How to Use

• RO and soft water: add CalMag Pro to plain water first, before any base nutrient, and stir well.
• Coco: use with every feed, as coco holds onto calcium and can leave plants short early on.
• Soil: use where your supply is soft or filtered and leaves are showing shortage.
• Mixing order: CalMag Pro, then base feed A, then B, then boosters - one at a time, stirring between each.
• pH: check and adjust only once the full solution is mixed, as adding minerals moves the reading.