Abstract: An injection pump comprising a barrel and plunger type tubing pump for pumping liquid from a deep borehole through tubing while injecting a treating liquid down through a hollow sucker rod. Just above the traveling valve is a blender coupling means. The hollow passage through the sucker rod communicates through an injector pipe to the top of a shallow bore in the top of the blender coupling means. There are two drilled openings through the wall so that liquid pumped down the sucker rod passes through the wall into the annular space between the traveling valve and the barrel where it can mix with the entering well liquids in a mixing zone between the traveling valve on the bottom end of the plunger and the standing valve of the barrel.