For the last 2 weeks my turtle has been making a whining noise. He repeats it about 9 times in a row each lasting about half a second. The only weird thing is he does it late at night. Never during the day. Usually when I turn my lights off. I was thinking he was scared of the dark so I tried a light next to the tank over night. He still made the noise. So I tried a brighter light. He still made it. And he only does it after about 11 pm. He is a yellow bellied slider around 1.5-2 years old. He has another turtle in the tank around the same age and species. Why are they making this noise. They have 60 gallons of water. They have a platform big enough for five turtles. A heat lamp only on during the day. A bunch of rocks cleaned regularly. A bubbler and a strong filter. Please don't give bs answers. Only ones that will inform me or help me.