I was also told to use the pump at least once a day. It is a definitely a time commitment but I was determined to do everything possible to ensure a good recovery. Yes, nocturnal erections are a very good sign. I found personally that the best erections at first were the nocturnal ones. The pump will only draw blood into the penis. Unless you use the rings, you need to be sexually aroused to maintain the erection once the vacuum is released. I found that working on arousal during the pumping also speeds up the action of the vacuum.