In addition, volatile oils are strongly scented and may mask feces and urine odors in the cage. In an aquarium or other enclosed environment, ammonia and other toxic gases, which are heavier than oxygen, sink to the floor where the animals are living. This disastrous situation may cause respiratory conditions to deteriorate rapidly. | In addition, volatile oils are strongly scented and may mask feces and urine odors in the cage. In an aquarium or other enclosed environment, ammonia and other toxic gases, which are heavier than oxygen, sink to the floor where the animals are living. This disastrous situation may cause respiratory conditions to deteriorate rapidly. |