Natural Seaweed Extract Flake, 100% water soluble, organic fertilizer 1.Black powder 2.Water soluble 3. Alginic Acid=8-15% Natural Seaweed Extract Powder, 100% water soluble, organic fertilizer China patent no.: 03112663.6 Product character:Black or brown flake, water soluble, pH=8-10Main ingredient: Alginic Acid: 8-15%, organic matter≥50%, N≥0.5%, P2O5≥3.0%, K2O:18-22%, much secondary element ...