I have put Nacho on a diet per the recommendation of the vet (15 lbs). He's a rescue stray that climbed into my car engine and was engine burned and we nursed to health.
I joke that he is an emotional eater. He and his brother Rigby get 1/8 cup dry cat food in the morning at 0600 when I leave for work and the another 1/8 cup in the evening when I return somewhere between 1930-2000 (7:30pm and 8:00pm) but sometimes later as I am an RN.
On days that I am home I don't notice Nacho eating from Rigby's bowl but I suspect that he is because he isn't losing any weight and he has been on this diet for 1 year now.
I've looked into the feeders that feed according to the microchip in your cat but so far have only been able to find models that feed for one cat and are $180 so to buy 2 is crazy.
To separate them geographically would stress them very badly as they are very very closely bonded even though they are 7 years apart and like I said I am away from the home for very long period of time when I am working. I am open to suggestions. Thank you!