The intake for the pump has this drop down plastic block that can be totally removed from the unit giving access to impeller and shaft without removing the jet, this hangs down as a water trap a little, but inside it also has a square step that cannot possibly be good for flow into the jet, it is only 3mm wide but none the less a step where water entering the unit will be hitting creating drag and thus rubbing me of speed.

Will take a vid of the little beastie after work tomorrow

for some reason shipping from US to NZ is crazy prices, but shipping from say china is way cheaper.