This is especially important if treatment is by slow sand filters.

The most common type of filter is a rapid sand filter.

This removal showed to be comparable to that of the slow sand filter.

He illustrated water filtration experiment by using three pairs of sand filters.

Slow sand filters do not require chemicals or electricity to operate.

Slow sand filters, due to their simple design, may be created diy.

Due to the low filtration rate, slow sand filters require extensive land area for a large municipal system.

He squatted on the beach and let sand filter through his fingers.

Blake is asked what a sand filter would cost.

"For most people, a sand filter will do the job," she said.