Vivosun Cal+Mag+Iron (2-0-0) Plant Nutrient | 1 Quart

Coco coir and reverse osmosis water are both low in calcium and magnesium. That shortfall shows up as blossom end rot, interveinal chlorosis, leaf curling, and stunted growth, often mid-grow when it's hardest to recover. Vivosun Cal+Mag+Iron is a concentrated 2-0-0 liquid supplement that prevents and corrects these deficiencies at a dose of just 2–5 ml per gallon.

The formula blends calcium, magnesium, iron, and nitrogen, the key elements for efficient photosynthesis, strong cell structure, and healthy flower and fruit development. It's 100% water-soluble and works in hydroponics, aeroponics, DWC, coco coir, and soil. It's fully compatible with other nutrient lines and improves your plants' uptake of the other nutrients you feed. Use it at every growth stage, indoors or outdoors, as a root feed or a foliar spray.

Because the formula is so concentrated, a single quart goes a long way. At 2–5 ml per gallon, one bottle treats roughly 190–470 gallons of feed water, enough to carry most home grows through several runs. It mixes in seconds with no residue, so you can add it to your existing feeding routine without changing your schedule, then fine-tune the dose until your plants respond the way you want.