Ceramic litter boxes don’t need replacing regularly as they do not harbour bacteria
It is suggested that cat owners should change their cat’s litter box every year because they harbour bacteria which is impossible to fully remove through cleaning. The problem being that nearly all cat litter boxes are made of rigid plastic and become sractched.
Some are not. You can buy stainless steel litter trays. You can also buy ceramic litter trays. Both these will not harbour bacteria and can be cleaned more thoroughly than can rigid plastic.
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