I have a 75 gallon aquarium. From my observations, you should let it run for about two days before it becomes accurate. By then the water temperature will appear 5-8F lower than the scale you set.
Tetra HT Submersible Aquarium Heater: Efficiently Regulate Temperature with Electronic Thermostat
9 Review
Accumulative electric water heater Thermex Ceramik 50 V, white
11 Review
YukiHalu Mini Submersible Aquarium Heater With Thermometer And Temperature Controller - 25W, 50W, 100W, Or 200W Options For 5-40 Gallon Fish Tanks
25 Review
Convector Electrolux ECH/T-2000 M, white
21 Review
Mini pump Xiaomi Mijia Electric Pump 1S, plastic, black
55 Review
Steam cleaner Deerma Deerma DEM-ZQ610 EU, white/red
68 Review
𧲠Efficient Magnetic Fish Tank Cleaner: KEDSUM Floating Clean Brush with Handle Design
34 Review
Greenpro Micranthemum Monte Carlo: Live Large Pearl Grass Aquatic Plant In Tissue Culture Cup For Freshwater Fish Tanks And Aquariums
49 Review