What characteristic distinguishes fine sand from coarse sand regarding filter runs?

Fine sand permits longer filter runs primarily due to its smaller particle size compared to coarse sand. This smaller particle size increases the surface area available for filtration, allowing finer particles to be captured more effectively. Additionally, fine sand has a greater ability to retain water and suspended solids, which creates less resistance to water flow over time.

In filtration systems, this characteristic enables fine sand to maintain effective filtration over extended periods before becoming clogged. The finer particles can trap not only larger particulates but also smaller impurities, thus holding their effectiveness for longer durations.

Conversely, coarse sand tends to have larger voids between the grains, which can lead to less effective trapping of smaller particles and rapid flow through the filter media. As a result, filters made with coarse sand may require more frequent cleaning or replacement because they become less effective at holding back contaminants sooner than their fine sand counterparts.