How Long Does Hills Dry Food Last. 1.5 nulo grain free dry cat & kitten food; 1.6 purina one urinary tract health formula cat food;
1.3 blue wilderness high protein grain free; If it’s a warm day, however, say about 50 degrees f, you shouldn’t leave dry food out more than four hours. Leading pet food manufacturer purina suggests removing uneaten wet food after one hour, while hill's says it's safe to leave the food out for up to four hours at room temperature.