Hello, I have a 120 that is just starting to take off. Although, I’ve always had temperature problems in the future of this system, either too high (consistently being 81.1) but now being as the colder seasons are just ahead, my system is running around 74-76. (I usually set my heater at 78). Should I be concerned about the unstable temperatures? (As I am writing this, it is running at 73.6) would colder temperatures affect corals in any way?