This seems to happen everytime the one cat goes in. I think it is the male and he is about 12lb's and may feel he can't fit in there, tho once he is done he goes all the way in to turn around.
Also, one of them leaves, him I think, more them pee on the entrance and the lower drawer.
We have 4 cats, and a few hours a day we have 5 cats as my daughters cat goes in the yard and comes up for a vist off and on all day.
I was hoping the drawer would be large enough to not have to empty it more then once every 5 or 7 days. AS it is, every day to day and a half we have to, as it piles up on one side. It is a bit of a mess to clean as I have to 'dry' it out and deod. it as the one cat keeps peeing on the dang drawer! *sigh*
It is still better then scooping, as that is something I did once a week, in an open box, in the living room, with 4 cats. I hated it, if I could be sure the cats would stay in our fenced in yard, I would put a cat door in and NEVER use alitter box! (I fear I am also very lazy.

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I have also noticed that some of the litter gets wet and sticks to part of the 'rubber' that is under the litter. They are use to one of those large courner litter boxes (the one that has the 'lid' that is the same that fits on top.) and they get 10 lb's of litter everytime it is filled up clean.
Do I need to get papers or something to put in the drawer, I guess I could get some of that pine litter and put it right where the 'pee' makes it into the drawer, when I take the bag out I just put the open bag on the floor and empty the 'litter' into it. That may keep it from getting wet in the drawer. Any ideas?
I have (glad or hefty) 13 gal. bags, the ones with the flaps, and it has been treated with something to keep the smell down. Even if I have to use a bag every day that is still only 3 or 4 bucks for a months worth. True, the .99 cent boxes would be even cheaper but I am trying this one first.
KattB