GROW!T Loose Premium Coco Fiber is a superior quality, 100% natural coir hydroponic growing medium, processed and manufactured under strict quality standards. GROW!T Loose Premium Coco Fiber is a special blend of coir that is buffered, treated, and enriched with micronutrients. The strategic addition of just the right amounts of calcium and magnesium actually displaces sodium and excess potassium, creating a safe and super-fertile substrate. Its low EC and stable pH make this coir such a supreme hydroponic and soilless medium that based on our testing, we believe it is the best loose coco coir on the market today.