Night Temps

[Big_V]

Ive decided that im gonna get a brazilian rainbow at the reptile show on the 22nd. Im just wondering about the various temps. Ive read alot of the debating thats out there and i think keepin the DTH at around 85-87 should be fine and the ambient should stay around 80-82. But i was wondering what temp is okay for at night time. Like what is the lowest temperature that should occur on the cool side of the tank at night. In my setup I have now it gets to 74 at night on the cool side. What are your guys thoughts ???
Cheers,
Ryan