Abstract: Filtering systems can process wastewater to provide a primary output of clear water and a secondary output of sludge. The filtering systems are compact, optionally mobile and optionally truck-mountable, and have a high throughput capacity and cleaning effectiveness. For a system having a volume VS, and for wastewater having a TSS content of TSS1 and a COD of COD1, the primary output may have a TSS<1% of TSS1, a COD<2% of COD1, and a turbidity of <1, or 0.5, or 0.3 NTU. The system may receive the wastewater at a flow rate F1 and provide the primary output while receiving the wastewater, and F1/VS may be ?0.2 hr?1. F1 may be ?1 L/sec, and VS may be ?5 m3, or ?30 m3, or in a range from 20-30 m3. The primary output may have a flow rate ?40%, or 50%, or 60% of F1.