Pool pumps, along with the pool's filter, keep your pool clean. A pool pump cleans a pool by circulating water through a basket and a filter to trap debris and dirt. The pump then recycles the clean water back into the pool. Pool pumps are available in different sizes, speeds and pumping capabilities. A different pool pump will be used depending on the pool's size, amount of water and if it's inground or above ground. When purchasing a pool pump you will pay more for a better quality pump, with a more efficient filter and a longer warranty. Pool pumps range from $70 to $500 online. Pool pumps for inground pools are obviously more expensive than pumps for above ground pools.