What size pump do I need for a flat pool cover?

A 1/4 HP pump is usually enough for a flat pool cover. Flat covers don’t hold much water, so 1/4 HP clears it quickly without being overkill. A 1/3 HP works for more speed or longer hose runs, but 1/6 HP is too slow. Avoid tiny pumps or oversized ones like 1 HP.