PBP is not all chem. Its a Natural/Organic based nutrient.. I have to use a recerc pump to keep the Organics from falling out of suspension. PBP has had some serious debates. It all comes down to Money. To get there Product approved for OMRI certification they had a few NATRAL ingredients that where not on there list. They could have had them added but the cost was way to high and decided the certification was not needed..I agree .... I use this to make my own cal/mag