(1) For Multi-Fill products to work to their maximum, whether it be a cap or a mag roller device, it's important that it fits and seals against the cartridge, without any air flow being allowed to escape. Any breach of a seal will slow the air exchange between the toner bottle and the cartridge, thereby rendering the filling process less effective.

(2) The internal volume of bottles does not always allow for a proper aeration of the toner. If sections of the toner aren't totally aerated then blockages will occur. Remember toner suppliers are now putting 500 grams of 600dpi toner in bottles that were previously used for 350-380 gram toner loads.

Solution A:- Just give the bottle a gentle sqeeze and release to help aerate the toner and promote toner flow again. (see Photos)

Solution B:- There are some toners that aerate extremely well and need to be given time to settle in the hopper to allow the full quantity to pour. Leave the hopper in a rack and go on with all the other tasks related with this cartridge, allowing it to fill when the toner has settled in the hopper.