If you are using MAM anti-colic bottles, where you can unscrew the base (or similar brands where you can unscrew the base of the bottle) with the Bottle Washer Pro we do not recommend removing the base of the bottle.
If you remove the base of the bottle you are left with a cylinder, similar to the image below. The Bottle Washer Pro is unable to clean the cylinder effectively, as the spray jets will miss the edges of the bottle.
By leaving the base attached this will ensure that the bottle is cleaned effectively.
* Do make sure to remove the silicone vent from the base and place this on the top rack
