More litter is not automatically better. A useful depth lets the cat dig while remaining compatible with the tray and litter being used. For an automatic unit, the manufacturer's fill instructions take priority over a general rule intended for ordinary trays.
Use general guidance as a starting point
Cats Protection describes around 3 cm as a depth many cats prefer in an ordinary tray. This is not a universal setting for every litter material or machine. Check the litter packaging and tray instructions, then observe the cat's response.
Keep the surface level
After routine scooping, restore the intended depth rather than adding a large amount only to one side. Check that the cat still has the usable space and entry access needed. A deeper fill can reduce the effective height of the tray's sides.
Follow automatic-unit limits
For a unit such as The Bothy, confirm the compatible litter and specified fill level before use. Do not infer these from the published interior capacity or add extra litter to compensate for a cleaning problem.
Change one factor at a time
If you are assessing a preference, avoid simultaneously changing the tray, litter type, location and depth. Keep a suitable familiar option available. A sudden toileting change needs veterinary advice rather than repeated experiments with the fill level.
Compare The Dome and The Bothy by their actual format and instructions. Confirm the details that affect daily use before ordering.
