This book discusses the possibility of combining Mangifera indica and Phoenix dactylifera seeds powders as coagulants in wastewater treatment. In the study, both seeds were characterized for their composition, active compounds and proximate constituents using Atomic Adsorption Spectroscopy (AAS), Scanning Electron Microscopy (SEM) analysis, and X-ray Diffraction (XRD) analysis. Jar test was carried out using the seeds extracts separately and in combination at varying dosages and the Electrical Conductivity EC, Total Dissolved Solids TDS, Chemical Oxygen Demand COD, Biochemical Oxygen Demand BOD, Turbidity, temperature, pH, and total coliform were measured with every varying dosage. Isothermal studies using Langmuir and Freundlich isotherm models were carried out, and kinetic behavior for the removal of BOD using the seed powders over certain concentration ranges was studied using the Pseudo-first and second order kinetic models. The study has shown that Mangifera indica seed and Phoenix dactylifera seed powders can be used as viable coagulants for water and wastewater treatment.