I have a ~120gallon setup, so based on recommended heater sizing I got 2x300W BRS titanium heaters on an inkbird controller. I also have an Apex for backup temp monitoring. The BRS website recommends 300W for "up to 100gal" and also put out a video awhile back that suggeated 2 smaller heaters...
Brand New In Box Finnex Deluxe 300watt Titanium Aquarium Heater with Cover - 40-80 Gal - TH-300S
Wattage: 300w
Power: 115v
Tank Size: 40-80 gal
Heating Tube: 10"
Cord length: 74"
Requires separate heater controller unit
$30 shipped
Brand New In Box Finnex Deluxe 300watt Titanium Aquarium Heater with Cover - 40-80 Gal - TH-300S
Wattage: 300w
Power: 115v
Tank Size: 40-80 gal
Heating Tube: 10"
Cord length: 74"
Requires separate heater controller unit
$30 shipped