My kitchen waste pipe discharges through the back wall of the house.
Until yesterday it used push-fit connections; one of these had given
way and waste water has been discharging down the wall. I've replaced
the lot with cemented and compression joints, but there's quite a bit
of green fungus on the outer wall under where the pipe passes through.
The bricks and mortar seem to be in good condition, but is there a
recommended fungicide suitable for brickwork?

Thanks -
--
Frank Erskine