What action can be taken to address high effluent suspended solids in trickling filters?

To address high effluent suspended solids in trickling filters, decreasing circulation is an effective action. When circulation is decreased, the flow rate of wastewater through the filter is reduced, allowing more time for solids to settle and be captured by the media within the filter. This adjustment can improve the efficiency of the biological treatment process, as it gives the microorganisms more time to break down organic material before the effluent is collected. It helps in enhancing solids removal and contributes to better overall water quality.

The other choices either do not directly target the problem of high suspended solids or may lead to unintended consequences. Flushing out the distributor arms may temporarily alleviate blockages but doesn’t address the underlying issue of effluent quality. Reducing the number of weeds is not directly relevant to suspended solids, as it pertains more to overall maintenance of the filter system. Flooding the filter would likely exacerbate the problem by increasing flow rates and potentially causing more solids to bypass filtration, making it counterproductive in this context.