Polymer mixing apparatus strips oil from polymers in an oil phase continuous emulsion and at least partially hydrates the polymers by injecting the emulsion and a pressured aqueous solution into a mixing zone. More specifically, the apparatus is a balloon catheter comprising an expandable balloon with a pouch around at least a portion of the balloon. If the screen option is valid for the index type, the user is notified about the changes that will be made and the effect of those changes.