Shower water reflux

[TiggerToo]

An annoying issue: Tigger's shower pump works well, but there is always half a cupful of water which re-emerges from the pipe, presumably the left-over in the pipe leading from the pump to the waste inlet. Can anyone suggest a solution to this? I currently have to mop up with a sponge and a cloth, but it is not very effective or convenient.

 

[Piers]

The problem can be eliminated if a pump is installed which uses 'duck bill' non-return valves, provided the pipework from the shower drain to the pump is no higher than the shower drain. Something like this. Water in the pipework between the pump and the outlet will be stopped from coming back into the shower tray.