EasyPro™ External Pump Skimmer Maximum Head Height_8 Feet you might consider Barley Straw

you might consider Barley Straw Concentrated Extract

4 gallons of water per cubic foot

For use with pumps with a 17' shut off or less and waterfalls up to 7' higher than the filter

make sure and verify all water parameters and rectify any issues before treatment

EasyPro™ External Pump Skimmer Maximum Head Height_8 Feet you might consider Barley StrawPSMEX Pond Skimmer For External Pumps Innovative skimmer designed for use with external pumps! Factory installed bulkhead fittings Pre plumbed for easy bottom drain connection, includes plug Design ensures all water goes through debris net Uses same debris net, lid and extension tube as PSMFB skimmer Black silicone included Multiple skimmers can be plumbed to one pump, ideal for odd shaped ponds where one skimmer is not enough Max Flow Rate: 75gpm