Hi I don't use this often but I signed up and thought I'd ask, I've done head gasket a while back I have put a pd150 on my fabia big front mount just trying to think of things that could have input, the coolant level keeps dropping brining the light on the dash but then when I open the bottle it rises up to half, I have seen few tiny wee black dots in coolant I don't see any leaks it seems so don't know what it could be....

Sounds like the head gasket/head lift to me. Is there pressure in the expansion tank when you remove the lid after it's been left overnight?

Yes but the head gasket has just been done with head skimmed all done not long ago

Well if there's pressure in the tank after standing all night it can't be much else. 

Did the head bolts get uprated to PD150 bolts?