In my new tank my rotala is really taking of, especially since I've started dosing low doses of easy carbo.
I did notice that the top part of the plant, 3-4 leaves closes for the night. Has anyone else noticed that?
Yup they close at night then open up during morning, water wisteria does this also. I have tried leaving the light on longer than normal to see if they will stay open longer. But no difference, those two plants let me know when to dim down the lights
As far as I know, the vast majority of stem plants do it. They develop their own Circadian rhythms based on your lighting settings. For example, if you observe your tank closely you will notice that stems begin to open up before lights on and close up before lights off.