Welcome to MFK. I hope you have an enjoyable experience here at MFK. Great site to be a part of and if you are wanting any information on Malawi's don't hesitate to ask ASH. Great gal.
I agree with all saying the higher temp. Here in South Africa we work in degrees celsius and I run my tanks at 27-28C. I would not go anything above 30C as I have read that over 32C you stand a chance of killing off your fish.
Mine are happy at 79-80. my heater crapped once and I caught it at about 73 because I noticed everyone in there was sluggish looking. They don't like the cold.