Are you using softened water? Play around with your delutions of the rinse, cut it in half and see if you like the results. Maybe even use no end zone at all just hot water rinse the next week and then call back the customers and get their feedback.
Which model rotovac are you using? Does it have glides on it? Try wanding the spots really well and see if that helps. Are the stains old? Maybe your spotting agents are not getting all the way down to the base of the fiber.
Which model rotovac are you using? Does it have glides on it? Try wanding the spots really well and see if that helps. Are the stains old? Maybe your spotting agents are not getting all the way down to the base of the fiber.