This study investigated the effectiveness of plant based materials Moringa oleifera (Moringa) seeds and Musa cavendish (banana peel) for removing heavy metals namely lead (Pb), nickel (Ni) and cadmium (Cd) from contaminated groundwater samples. Tests were carried out with individual and combined biomass doses at neutral pH condition (7.0). The optimum biomass doses were 200 mg/L for single biomass and 400 mg/L (200+200 mg/L) for combined biomasses used for adsorption isotherm studies and linearized according to Langmuir and Freundlich adsorption isotherm models. Moringa seeds exhibited the best removal of Pb while the combined solution was the most effective for Ni and Cd. In terms of adsorption studies, Freundlich model described the Pb adsorption better than the Langmuir model for all the tested biomasses. However, the Langmuir model demonstrated the Ni adsorption on Moringa better. Both models showed negligible differences in the coefficient of determination (R²) when applied for Ni and Cd adsorption on banana peel and combined biomasses, suggesting that there were multiple layers on the biomass interacting with the metals. Overall, these findings indicate that there is a possibility of multi adsorption sites interacting with Pb, Ni and Cd due to the good fitness of the Freundlich model. The study shows that Moringa seeds, banana peel and their used combination have the potential to be used as a natural alternative to the chemical coagulant for removing the Pb, Ni and Cd from drinking water.