What they said. Go to a familiar place of known cover and adjust ONE thing at a time (brightness, gain) until you optimize the display. I say that so you don't do too much and get frustrated in the beginning. Follow scrat's advice. Good to see your Garmin cv ducer returning bait balls and fish in the 30-45' ranges. You're not far from maxing it. Every day, every lake, every season and every bottom can and often will make a diff. Learn what and how to tweak. And just accept that you may need to do it daily, or within the day. None of them are 'set and forget'. I like lighter colors for clear days and more subtle ones for darker days, but find what suits you. Good luck