The experiment looked at how adding certain substances can help membranes work better and avoid getting clogged. They found that adding 4mg/L and 10mg/L of a specific substance helped the membrane work well again after cleaning, while without it, the membrane only worked at 40% capacity. The type of layer that forms on the membrane during filtering affects whether adding the substance helps prevent clogs. If the substance forms a layer on the membrane, it stops clogs, but if it doesn't, clogs can still happen.