80F is nothing to worry about. I run my tank purposely at 80. When you hit 84 is when you need to start worry.
Oh, I was referring to the air temp inside our house, not our tank temps. Our house is almost 50 years old, so when it gets to be > 100F outside for more than just a couple of days, we don't have a choice but to let the air temp inside climb from around 76 - 77F up to 80F, unless we want a $400+ electric bill.
Even with the air temp in the house at 80F, I can keep our sw tank below 84F without too much problem. It usually just means turning the fan up that blows across our sump.