Ok I managed to find a way. In case anybody else has the same problem this is what I did.
The mixer tap had a plastic screw in spout (if you see what I mean!). Fortunately the screw size was exactly the same as the hozelock screw in adapter so I just screwed it in.
All is now fine...
I drained my cold water tank to clear out some of the rubbish at the bottom. Now I am only getting a dribble from my cold water tap in the bath.
Looking at other posts I guess it must be an air lock. The advice I have found say to clear it using mains pressure. My problem is that the tap in...