Hi,
No you dont have to change_replace anything, just turn the box upside down , once is updise down smack a little bit the the box so any urine left will fall as well and then put back the box in the original position and pull the " removable scoop" and place the dirty stufff in a bag....
put back the scoop and then make sure the litter is all the way down in the litter box....its so easy, I clean 3 times a day...and i am not even using much my robots ( saving energy....trying to go green here...lol)
I am very happy, I will be asking for 2 more soon..
check this video in amazon.com
http://www.amazon.com/review/R31TV82CVSSVZ1/ref=cm_cr_pr_viewpnt#R31TV82CVSSVZ1
Price:
$24 at radio fence..( get the large size)
amazon$ 34,60
So do you just turn the box upside down and it scoops the waste away? Also, do you have to replace the grill thing each time it needs to be disposed? Or do you have to clean the grill thing on occassion?