RFID describes a technology, not universal compatibility
Some feeders read a dedicated collar tag; others read supported implanted microchips. Confirm the exact identifier before assuming the household's existing chip or tag will work.
Start with the pet conflict
Access control helps when one animal steals another's food or diets differ. It adds little when every pet safely shares the same food and schedule.
Count feeders, tags, and floor space
A one-tag-per-feeder design can require several units. Include reader mats, lid clearance, outlet access, cleaning space, and replacement tags in the real cost.
Keep a supervised fallback
A lost tag, weak battery, jam, or hesitant pet can interrupt access. Introduce the feeder while someone is present and preserve a safe backup feeding plan.