My Fitbit calls me  "The Parrot" for my light sleeping habits. REM is fine, but light sleep comprises the majority of my phases. Total sleep is classified as "fair" at 6-7 hours per night. I'd like to boost deep sleep as my therapist says it's when the brain recovers. Other than boosting my total sleep time to the recommended 8 hours, has anyone had success with getting more deep sleep? On 900mg Lithium daily.