Yeah. It comes with litter. My litter robot sits in mine, but yours is still a good idea.
PetSafe ScoopFree Cat Litter Crystal Tray Refills for ScoopFree Self-Cleaning Cat Litter Boxes - 3-Pack - Non-Clumping, Less Mess, Odor Control - Available in Original Blue, Lavender, or Sensitive https://smile.amazon.com/dp/B000FEF10A/ref=cm_sw_r_cp_api_glt_fabc_8252YXK3QCRSF92F0EZR
I have one of those electric, self cleaning litter boxes and use disposable trays. https://www.amazon.com/PetSafe-ScoopFree-Self-Cleaning-Refills-Non-Clumping/dp/B000FEF10A?pd_rd_w=K45nC&content-id=amzn1.sym.bc622850-a717-4d94-96c3-7cc183488298&pf_rd_p=bc622850-a717-4d94-96c3-7cc183488298&pf_rd_r=XZY24RAX0BYKSKE1R2XZ&pd_rd_wg=JMaH6&pd_rd_r=c4b9fb21-4267-4518-a372-e6baf18f43cb&pd_rd_i=B000FEF10A&ref_=pd_bap_d_rp_1_i&th=1
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Worth every damn penny. I change the tray monthly. Just swap it out and put in the new tray. I usually hose off the electronic litter box, as well. So quick and easy. There are a few crystals that get on the floor right by the box, but my cat has never tracked this more than 3 feet from the box.