Problem is that the entire hose is at switching off the pump under pressure. Fault is that moronic arranged Rüsckschlagventil at the end of the hose. Since the development Heini have probably pumped in a few too many beers with the hose.
The hose securely holds longer if you have non-return valve worried myself (DIY 10 Euro) and this directly mounted to the suction flange of the pump. For this you can then remove the built-in hose and best throw away.
So the hose is then no longer under pressure when the pump shuts off. If the suction head is minimal, there is no problem if the tube should run dry any halfway clever garden pump pulls the water loose 2-3 meters in a few seconds again.
LG
Alex
