Van Cat Active Carbon Granules 8.5kg Cat litter This would be perfect if you find your tray is left quite smelly. As with all Van Cat litters, simply fill the tray to 7cm in depth, then scoop out the clumps as needed. Providing you top the litter back up, you will never need to empty the entire tray. The W225 series is our most popular series, it comes in 8 different scents, white active carbon and unscented. Its liquid absorption capacity is high and clumps very well due to the unique shape of the granules They are small and circular, forming a ball in the litter which makes cleaning the tray easier. Proving to be cost-effective and long lasting.