There is no difficulty for large-scale water filter systems to have a separate pump and a larger pipe specifically for backwash operation. Unfortunately, a similar set-up will be too troublesome and costly for home use. From many years of experience gained in household water filtration. Crosslink found that the required flow for service run at 3-5 gpm/sq ft can be altered upward if finer particle-size of sand is used, instead of the standard 0.6-1.2mm. With the increased rate of service run, we can bring the gap of service flow and backwash flow closer — therefore, eliminating the need for 2 different pumps to cater to the respective flow. Nevertheless, Malaysian city water is usually quite clean. With our domestic filters operating as a secondary filtration, we are able to take advantage Of Our filtered city water by performing frequent backwash — without the worry of fine sand congestion by large unfiltered dirt brought in by the municipal water. By doing so the tank size can also be reduced to match the required backwash flow.