Eichhornia Crassipes or commonly known as Water Hyacinth can help in the process of Phytoremediation. The paper deals with the effectiveness of Eichhornia Crassipes in purifying car wash water. For conditioning the car wash water further, we can also use alum. As water hyacinth roots have capacity to control the turbidity as well as the roots can settle so many sediments and also can fix Nitrogen present in the water. Post treatment condition of car wash water observed to be an economy and ecology friendly process. Amalgamation of biological, physical and chemical treatment can give us best results. Here we focused only on biological treatment method to purify the car wash water and make it reuse for the same car wash process.