Set my Reserator up yesterday and bled the system using a variety of methods listed on t'interweb:

1. Having the reserator the highest component in the system
2. Leaning the reserator 40 degrees each side

I am now sure all the bubbles are out and that the system is flowing properly.

However, the flow tube seems to stop wobbling occasionally, the orange indicator stays in the centre of the tube, so I know flow is still occuring (if you turn the pump off the indicator drops to the bottom of the glass). If you move the flow tube, it starts to move again.

Could this be a faulty flow tube?

Seems ok now some heat has been pumped through the system - it's waggling like a little fish!