Pipe Fittings - 5pcs PVC 1/2 inch to 8mm 10mm 12mm 16mm Hose Thread Connector For Air Pump Accessory Water Pump Joint Fish Tank Tube Adapter (1l2 inch-16mm(white)) - - Amazon.com
uxcell PVC Hose Tube, 10mm(0.39") ID x 13mm(0.51") OD 1.5m Clear Vinyl Tubing, Plastic Flexible Water Pipe - - Amazon.com
Inner diameter 3/8" 10mm 10 Ft 3 Meter PVC Clear Tubing Flexible Air Water Delivery Hose - - Amazon.com
15FT 10mm Inner Dia Clear Plastic PVC Hose Pipe Tube for Air Pump by Houseuse - - Amazon.com