In a feeder for feeding additives such as aluminium oxide or fluoride to aluminium electrolysis cells, the additives are fed to the electrolytic bath of the cell through a hole in the bath crust via a pipe stub. The hole is made by means of a crust breaker having a crow bar connected to a piston/cylinder device. The point feeder is made of a housing comprising an upper part, wholly or partly open to the surroundings, and a lower part closed the crust and other parts of the surroundings. The crow bar extends down through a guide in the form of a bushing, which is provided between the upper and lower part. Further, the pipe is attached to the lower part, or is provided under the lower part, for instance on the gas apron of the anode casing in a Soederberg cell.