Slight leak problem

Just recently refitted my water pump bled the system and noticed a slight leak on start up. Its been a couple of days since the pump was refitted and it only leaks when the car is cold from around that area. Once the car is up to temp the leak dissappears. None of the pipes seem to be leaking from what i can see from the front and all have had new clips on and are tight. The leak is from the water pump area. Any ideas on this would be great as i hate leaks lol
Thanks in advance

Was it a new pump or replacing your old one?  Could be worth checking the gaskets on the pump/thermostat housing or checking the core plug.  There's not a great deal of places for it to leak down there.  Have a go and let us know