Check Valves mount the pump in the Skimmer to maintain water in biological filters and keep beneficial bacteria hydrated Atlantic's Triton TR215CV Check Valve is the first and only specifically designed for water feature use

The Aquascape Dual Union Check Valve 2.0 effectively prevents backflow in ponds and water features while providing a professional pump and plumbing connection inside pond skimmers and Pondless® Waterfall Vaults.

Check Valve Dual Union 3″ – Just The Valve

The Dual Union 3″ Check Valve effectively prevents backflow in ponds and water features while providing a professional pump and plumbing connection inside filters and pump vaults.