This filter is special. It removes disolved metals and minerals from water. It is very hard to find a filter that does this well. Sediment filters will not do it. Good for 10,000 gallons. Perfect for hot tubs if you are on well water. Save money on hauling water in. Very simple to use, just attach to a garden hose, adjust valve to slow down water flow, and fill. * Using water that has metals or minerals in your hot tub or pool can cause extreme discoloration and build up. When disolved metals and minerals come in contact with chlorine or other oxidizing agents they react and cause the water to discolor. For example, iron will turn brown, cooper with turn green. Remove the problem before it gets in your hot tub rather than fight with it constantly after its in.