Red light is recommended for sleep time (if you use a night light) because it’s doesn’t interfere with baby’s circadian rhythm or release of melatonin.
When I first had Raiden I was so excited to use the new Hatch machine we had gotten from a family member. It had so many colors and sounds, I was thrilled. But I noticed a difference in how he slept based on how bright the light was and what the color was. So through further research (Facebook mom group) I learned about the red light! And haven’t turned back since! He sleeps so much better!
Average Ordinary Mom 