Whole House Water Filter Systems. Depending on the whole house water filter chosen they can remove or reduce chemicals, chlorine, heavy metals, herbicides, pesticides, bacteria, viruses, cysts, sediment, most colours, volatile organic compounds, bad taste and odours. Choose from Watermark certified big blue or big white whole home filter systems available in 10 inch x 4.5 inch or 20 inch x 4.5 inch sizes. Our premium range of whole house filters are also water softeners to remove scale buildup etc. Our systems are designed for high flow, are watermark certified and carry a 5 year warranty. Suitable for mains water, rain water, tank water, bore water and town water. For use with potable water.