Well well well, finally you've got around to doing something about the underpowered pump (or should I say pumps).
It's not like we haven't tried to convince you to do it, I mean, the first thread I remember of yours was concluded that you needed to either change the pump or unscramble the pipework.
So what can we take from this, some do heed the advice given to then, some take some time to implement it, and some, like Julian, struggle on defiantly for many years before giving in.