Clack WS-1 1.5 cuft calcite only acid neutralizer filter with a Top Dome Hole 10" x 54" poly tank with a 1.05" distributor tube and gravel underbed and 1" Noryl by-pass valve with either 1" MPT sch 80 PVC swivel elbow or 1" or 3/4" soldered brass plumbing connectors. I strongly suggest the swivel elbows. Free Shipping. $650