I have heard that low humidity helps keep the rat smells down. I have my rats in the snake room at about 50-60 humidity. I don't notice the smell in the air but once I leave the room my clothes smell really bad, even after a very short time (5 minutes or less). . I have 15 tubs going and I am cleaning them every 3 days. I built a carbon filter when I only had 5 tubs of rats and now with 15 tubs it cannot keep up with the smell. If low humidity will help I will buy a dehumidifier or move the rats to another location.
Basically I am looking for first hand knowledge on how humidity effects rat smells..
Richard