Lettuce Formula, Heavy Metals Tested, Water Soluble, 8-15-36, Best on the Market, Hydroponics Friendly Scientifically formulated with super clean raw materials and enhanced mineral nutrients Laboratory validated via ICP-MS by the Health Ranger Produces the world's most mineral-rich plants for eating or juicing Manufactured in the USA from raw materials sourced all over the world Nearly unlimited shelf life; lasts virtually forever in storage