I inherited an abandoned kitty around 8 months old...weighing around 5 lbs at the time. I always left water and food out....she ate when she wanted...flaked tuna put strain on her kidneys (proof in the blood tests before and after taking tuna away)....Cat, Princess, is 16 now...weighing around 5 lbs again (after getting to be around 6.5 - 7 during her years)...I got a companion cat, Snowy, when Princess was 11....As a 1 yr old, Snowy was a taller and larger cat...the two never became close unfortunately and after 5 years Ms. Snowy is now a fat 16 pounds...and Princess still small. Snowy intimidate Princess when I am not home (I can tell due to the different behavior when I get back from a trip where Princess won't get on bed or sleep in same place any more...which is upsetting and I am working to get Princess out from sleeping in my closets now....(bad Snowy, of course)....but, anyway....food has always been out....fresh wet food daily...I think as an only cat, it should not be a problem. This was low maintenance for me. Some like rigid schedules. I can't adhere to that with crazy work schedule. But, I know, Snowy needs more running around and.....maybe a tread mill for her next birthday (just kidding)...Happy holidays.