Advanced Nutrients Coco Coir Additives Big Bud Coco - 1 LReap the bud bulking benefits of Big Bud the worlds #1 bloom booster without risking nutrient imbalances in your coco coir grow. Big Bud Coco features a precisely dialed in PK spike to strengthen and bulk floral structures, plus magnesium, two forms of calcium, and diversely chelated forms of iron to prevent nutrient leaching from the grow medium. PK ratio is dialed in for completely compatibility with coco coir Magnesium, calcium, and chelated iron