SupreKelp 50oz Concentrate Makes 187 gallons of ready to use product* 3 species of kelp: Ascophyllum nodosum, Sargassum spp., Laminaria spp. 100% All Natural - Non-Toxic - Safe to use - ECO-Friendly Promotes strong rooting and vigorious growth. Similar to: Sea-Kelp 100 (Organics Rx), BioWeed (GenHydro), Raw Kelp (NPK)