This is going to be a noob question, but its been almost 3 years since Ive had a tank setup so please excuse my noobishness

Ive had my tank running for about 3 days. I got my lights and all setup. Just wanted to get all of my hardware up and tested. Anyway, the temp in my tank got up to 81 yesterday. Im going to say given that that 82-83 could be a max temp on a really bad day. Ive been running my lights longer then normal and on different cycles then I would with fish and such. (I normally turn them on around 9am just actintic, 11am full lights, 7pm back to actintics and then 9pm off)
Anyway, Im wondering what you guys would call a safe fluctuation. I can let it get cooler at nite and make it easier to stay cooler longer during the day.
Is 82-83 too high?
Im just missing the little things in my head on this now. (getting old)
Im going to keep reading, but just wanted to ask here as well. Thanks in advance.