I have a vacuum head and hose but couldn't get enough suction from the skimmer due to a poor seal.  I hope this will solve that problem!  My hose inner diameter is 1.5" (38 mm) and the skimmer basket lip is about 7" (180 mm).  

I wanted a balance of minimum print time and minimum filament so the model is designed at about 45º angle.  With 5% infill the adapter is quite rigid, more than is necessary for the suction produced by the water pump.

Thoughts?