He could be cruising partially because of temps.
70 is too cold.
The lowest should be 75-77F for a corn.
I have a hot spot of 84-86F, ambient around 77-78, and a 77 cool spot.
If it's that cold, you might want to wait until you have a CHE before feeding. They can regurgitate if temps are not good.
Sorry for the late response, I have been ill the past few days.