Water is essential to support daily life, ecosystem, environment, and development. Due to rapid industrialisation, population growth, and economic development, the water demand increases worldwide. For this reason, research is being conducted to find alternative sources of water for non-potable purposes. Domestic greywater is receiving much attention worldwide as a possible alternative water supply for domestic and productive purposes. This study aims to determine the water quality index (WQI) for domestic wastewater and evaluate the effectiveness of Iron Removal Media (IRM) and Cattail Typha Angustifolia plants in treating greywater. The domestic wastewater used for treatment was wastewater from laundry activities. There are two types of models designed to obtain different data for both media. The first model design is used with Iron Removal Media and the second model is with Cattail Typha Angustifolia plants. After the greywater treatments, the efficiencies of different treatments were observed and compared to the WQI standard. It was found that the removal efficiencies were 25% for biochemical oxygen demand (BOD), 23% for chemical oxygen demand (COD), 12% for total suspended solids (TSS), and 9% for pH using IRM. When Cattail Typha Angustifolia media was used, the removal efficiencies of 57% for TSS, 46% for COD, 45% for BOD, and 10% for pH were achieved. This study showed that using Cattail Typha Angustifolia plants as media for the greywater treatment process could be more effective as compared to IRM.

• Aghlmand, R., & Nezami, S. R. (2021, July 12-14). Evaluation of drinking water quality using WQI: A case study in Ardabil Province, Iran. In 12th International Congress on Civil Engineering (pp. 1-4). Mashhad, Iran.

• Al-Gheethi, A. A., Mohamed, R. M. S. R., Wurochekke, A. A., Nurulainee, N. R., Rahayu, J. M., & Hashim, M. K. A. (2017). Efficiency of Moringa oleifera seeds for treatment of laundry wastewater. In MATEC web of conferences (Vol. 103, p. 06001). EDP Sciences. https://doi.org/10.1051/matecconf/201710306001

• Al-Husseini, T. H., Al-Anbari, R. H., & Al-Obaidy, A. H. M. J. (2021). Greywater environmental management: A review. In IOP Conference Series: Earth and Environmental Science (Vol. 779, No. 1, p. 012100). IOP Publishing. https://doi.org/10.1088/1755-1315/779/1/012100

• APHA. (2017). Standard methods for the examination of water and wastewater (23rd Ed.). American Public Health Association. https://doi.org/ISBN 9780875532356

• Arifin, S. N. H., Mohamed, R. M. S. R., Ismail, N. R., Al-Gheethi, A., & Bakar, S. A. (2020). Effects of direct discharge of domestic greywater to nearby water body. Materials Today: Proceedings, 31(March), A126-A136. https://doi.org/10.1016/j.matpr.2021.01.038

• Bani-Melhem, K., Al-Qodah, Z., Al-Shannag, M., Qasaimeh, A., Qtaishat, M. R., & Alkasrawi, M. (2015). On the performance of real grey water treatment using a submerged membrane bioreactor system. Journal of Membrane Science, 476(February), 40-49. https://doi.org/10.1016/j.memsci.2014.11.010

• Byrne, J., Dallas, S., Anda, M., & Ho, G. (2020). Quantifying the benefits of residential greywater reuse. Water, 12(8), Article 2310. https://doi.org/10.3390/w12082310

• Department of Environment. (2010). Environmental quality report 2010. Department of Environment.

• Ebrahimi, A., Ehteshami, M., Dahrazma, B., Salari, M., & Fatehbasharza, P. (2021). Efficient Cd ( II ) ions removal from aqueous solution using peganum harmala and prosopis farcta seed as adsorbents. Journal of Environmental Treatment Techniques, 9(4), 728-736.

• Emery, C. M., Paris, A., Biancamaria, S., Boone, A., Calmant, S., Garambois, P. A., & Da Silva, J. S. (2018). Large-scale hydrological model river storage and discharge correction using a satellite altimetry-based discharge product. Hydrology and Earth System Sciences, 22(4), 2135-2162. https://doi.org/10.5194/hess-22-2135-2018

• Gafri, H., Zuki, F. M., Mohamad, Z. F., Affan, N., & Sulaiman, S. N. A. H. (2018). A study on water quality status of varsity lake and pantai river, Anak Air Batu River in UM Kuala Lumpur, Malaysia and classify it based on (WQI) Malaysia. EQA-International Journal of Environmental Quality, 29, 51-65. https://doi.org/10.6092/issn.2281-4485/7967

• Ghaly, A. E., Mahmoud, N. S., Ibrahim, M. M., Mostafa, E. A., Abdelrahman, E. N., Emam, R. H., Kassem, M. A., & Hatem, M. H. (2021). Greywater sources, characteristics, utilization and management guidelines: A review. Advance in Environmental Waste Management & Recycling, 4(2), 128-145.

• Gross, A., Kaplan, D., & Baker, K. (2006). Removal of microorganisms from domestic greywater using a recucling vertical flow constructed wetland (RVFCW). Water Environment Foundation, 2006(6), 6133-6141.

• Hasan, H. H., Jamil, N. R., & Aini, N. (2015). Water quality index and sediment loading analysis in Pelus River, Perak, Malaysia. Procedia Environmental Sciences, 30, 133-138. https://doi.org/10.1016/j.proenv.2015.10.024

• Ho, K. C., Teow, Y. H., Sum, J. Y., Ng, Z. J., & Mohammad, A. W. (2021). Water pathways through the ages: Integrated laundry wastewater treatment for pollution prevention. Science of the Total Environment, 760, Article 143966. https://doi.org/10.1016/j.scitotenv.2020.143966

• Huang, Y. F., Ang, J. T., Tiong, Y. J., Mirzaei, M., & Amin, M. Z. M. (2016). Drought forecasting using SPI and EDI under RCP-8.5 climate change scenarios for Langat River Basin, Malaysia. Procedia Engineering, 154, 710-717. https://doi.org/10.1016/j.proeng.2016.07.573

• Jefferson, B., Palmer, A., Jeffrey, P., Stuetz, R., & Judd, S. (2004). Grey water characterisation and its impact on the selection and operation of technologies for urban reuse. Water Science and Technology, 50(2), 157-164.

• Jiang, J. Q., He, Q. L., Acheampong, B., Balazs, T., Bancroft, T., & Sciences, P. (2009). Feasibility study on grey water reuse. In Proceedings of the 11th International Conference on Environmental Science and Technology (pp. 497-505). Aqua Envio Technology Transfer.

• Laaziz, A., Kouda, I., Barhoun, A., & Draoui, K. (2021). Kinetic, isotherm, and thermodynamic study of methyl orange adsorption on raw clay from North of Morocco. Journal of Environmental Treatment Techniques, 9(3), 675-685.

• Li, F., Wichmann, K., & Otterpohl, R. (2009). Review of the technological approaches for grey water treatment and reuses. Science of the Total Environment, 407(11), 3439-3449. https://doi.org/10.1016/j.scitotenv.2009.02.004

• Lós, R., IzbékinéSzabolcsik, A., & Bodnár, I. (2020). Investigations of detergents and metal components for supporting the effective treatment of greywater. Műszaki Tudományos Közlemények, 13(1), 114-117. https://doi.org/10.33894/mtk-2020.13.20

• Mahmud, M. H., Lee, K. E., Mokhtar, M., & Wahid, M. A. (2018). Technical strategy for revitalizing urban river water quality through structural approach at national university of Malaysia (UKM) Bangi campus, Selangor, Malaysia. Applied Ecology and Environmental Research, 16(3), 2681-2699. https://doi.org/10.15666/aeer/1603_26812699

• Mallick, Z., Hossain, R., Ayshi, F. T., Tahsin, A., & Mallick, S. P. (2021). Water quality index (WQI) for evaluation of the surface water quality of Bangladesh and prediction of WQI from limited parameters. Journal of Environment Protection and Sustainable Development, 7(2), 56-64. https://doi.org/10.5281/zenodo.5152752

• Matchaya, G., Nhamo, L., Nhlengethwa, S., & Nhemachena, C. (2019). An overview of water markets in Southern Africa: An option forwater management in times of scarcity. Water, 11(5), Article 1006. https://doi.org/10.3390/w11051006

• Mir, S., Arafat, M., Zularisam, A., & Edriyana, A. (2017). Characterization of Chini Lake water quality with Malaysian WQI using multivariate statistical analysis. Bangladesh Journal of Botany, 46(2), 691-699.

• Muhamad, M. H., Abdullah, S. R. S., Hasan, H. A., Bakar, S. N. H. A., Kurniawan, S. B., & Ismail, N. I. (2021). A hybrid treatment system for water contaminated with pentachlorophenol: Removal performance and bacterial community composition. Journal of Water Process Engineering, 43(June), Article 102243. https://doi.org/10.1016/j.jwpe.2021.102243

• N’diaye, A. D., Bollahi, M. A., & Kankou, M. S. (2021). Ultrasound-assisted adsorption of copper from aqueous solution by using natural mauritanian clay as low-cost adsorbent: A preliminary study. Journal of Environmental Treatment Techniques, 9(3), 636-641.

• Nguyen, H. T., Błażejewski, R., & Spychała, M. (2020). Greywater treatment in lamella settler and combined filters. Desalination and Water Treatment, 203(November), 202-210. https://doi.org/10.5004/dwt.2020.26201

• Ntibrey, R. A. K., Gyasi, S. F., & Kuranchie, F. A. (2021). Assessment of greywater reuse as a potential mitigation measure for water shortages and sanitation problems in senior high schools. Water and Environment Journal, 35(1), 242-251. https://doi.org/10.1111/wej.12622

• Oron, G., Adel, M., Agmon, V., Friedler, E., Halperin, R., Leshem, E., & Weinberg, D. (2014). Greywater use in Israel and worldwide: Standards and prospects. Water Research, 58(0), 92-101. https://doi.org/10.1016/j.watres.2014.03.032

• Oteng-Peprah, M., Acheampong, M. A., & DeVries, N. K. (2018). Greywater Characteristics, treatment systems, reuse strategies and user perception - A review. Water, Air, and Soil Pollution, 229(8), 1-16. https://doi.org/10.1007/s11270-018-3909-8

• Patankar, S., Chavan, J., Dharane, A., Patade, S., & Kate, S. (2020). Greywater treatment using wetland: A review. International Journal of Innovative Research in Science, Engineering and Technology (IJIRSET), 9(4), 1334-1337. https://doi.org/10.13140/RG.2.2.30417.35689

• Prasad, R., Sharma, D., Yadav, K. D., & Ibrahim, H. (2021). Preliminary study on greywater treatment using water hyacinth. Applied Water Science, 11(6), 1-8. https://doi.org/10.1007/s13201-021-01422-4

• Rosa, G., & Ghisi, E. (2021). Water quality and financial analysis of a system combining rainwater and greywater in a house. Water, 13(7), Article 930. https://doi.org/10.3390/w13070930

• Sanou, Y., & Pare, S. (2021). Comparative study of adsorption capacity of two mixed materials for arsenic remediation. Journal of Environmental Treatment Techniques, 9(3), 559-565.

• Sharma, A., & Wasko, C. (2019). Trends and changes in streamflow with climate. In Trends and Changes in Hydroclimatic Variables (pp. 275-304). Elsevier Inc. https://doi.org/10.1016/b978-0-12-810985-4.00005-0

• Singh, S., Ahammed, M. M., & Shaikh, I. N. (2021). Combined coagulation and intermittent sand filtration for on-site treatment of greywater. In IOP Conference Series: Materials Science and Engineering (Vol. 1114, No. 1, p. 012031). IOP Publishing. https://doi.org/10.1088/1757-899x/1114/1/012031

• Sulaiman, N., Zubairi, S. I., Sani, N. A., & Kasim, Z. M. (2020). The efficacy of treated water from water filtration machines for safe drinking water supply in Bandar Baru Bangi and Kajang, Selangor. Journal of Food Quality, 2020, Article 3536420. https://doi.org/10.1155/2020/3536420

• Szymanski, N., & Patterson, R. A. (2003). Effective microorganisms (Em) and wastewater systems. In Best Management Practice Conference (pp. 347-354). Lanfax Laboratories Armidale.

• Talaiekhozani, A., Banisharif, F., Bazrafshan, M., Eskandari, Z., Chaleshtari, A. H., Moghadam, G., & Amani, A. M. (2019). Comparing the ZnO/Fe(VI), UV/ZnO and UV/Fe(VI) processes for removal of reactive blue 203 from aqueous solution. Environmental Health Engineering and Management, 6(1), 27-39. https://doi.org/10.15171/ehem.2019.04

• Uddin, S., Khalifa, R., & Alam, A. (2019, January 19-22). Grey water treatment using glass filter media. In 2nd International Conference on Water and Environmental Engineering (iCWEE-2019, Dhaka) (pp. 94-108). Dhaka, Bangladesh.

• Utaberta, N., Handryant, A. N., & Mydin, M. A. O. (2015). An analysis of grey water treatment system in the National University of Malaysia Mosque. Applied Mechanics and Materials, 747(June 2017), 313-316. https://doi.org/10.4028/www.scientific.net/amm.747.313

• Zaiedy, N. I., Karim, O. A., & Mutalib, N. A. A. (2016). Water quality of surface runoff in loop two catchment area in UKM. Jurnal Kejuruteraan, 28(1), 65-72. https://doi.org/10.17576/jkukm-2016-28-07