Pool owner sometimes find that their fill water is putting iron into the pool water. Especially when the fill water is coming from a well. Iron accumulates in pool water and iron levels over 0.3 ppm can cause staining.
Many garden hose water filters for hoses have a flow rate of 2 gpm. One member put together two Pentek 150237 #10 Big Blue Filter Housing in series with a PentekWPX5BB97P 5 micron filter followed by a Pentek WP-5BB97P 0.5 micron filter with a flow rate of 10 gpm for his fill water.[1]
They screw on the end of a garden hose before the water goes into the pool. After topping up the filters are removed and dried in the sun to avoid any kind of mildew growth from wetness.
