I had them in my 100 gallon hex tank on the lowest setting. After about a week or two it melted and cracked a panel of my tank. I will not use for free. Luckily I was home when this happened and no fish were harmed from using this product. However, I don't have a very expensive aquarium.
Faucet water heater with display
13 Review
π Fluval E300 Electronic Heater - 300W Advanced Aquarium Heater for Tanks up to 100 Gallons (A774)
9 Review
Tetra HT Submersible Aquarium Heater: Efficiently Regulate Temperature with Electronic Thermostat
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Sectional radiator Royal Thermo PianoForte 500, number of sections: 10, 11.7 m2, 1170 W, 800 mm.
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Greenpro Micranthemum Monte Carlo: Live Large Pearl Grass Aquatic Plant In Tissue Culture Cup For Freshwater Fish Tanks And Aquariums
49 Review
π U-BCOO Aquarium Gravel Cleaner Fish Tank: Manual Siphon for Efficient Filter Gravel Cleaning and Water Change in Tanks
22 Review
Steam cleaner Deerma Deerma DEM-ZQ610 EU, white/red
68 Review
π§² Efficient Magnetic Fish Tank Cleaner: KEDSUM Floating Clean Brush with Handle Design
34 Review