![Help. So this is the second digital thermometer I've bought that says my tank is at 90F degrees. My top fin one has always said my temp is around 76-78F. Why is Help. So this is the second digital thermometer I've bought that says my tank is at 90F degrees. My top fin one has always said my temp is around 76-78F. Why is](https://preview.redd.it/kz8aqwkyion91.jpg?auto=webp&s=29bb84df20c11187eac50b6001d57739ba3d3f5b)
Help. So this is the second digital thermometer I've bought that says my tank is at 90F degrees. My top fin one has always said my temp is around 76-78F. Why is
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Amazon.com : Marina Deluxe Floating Thermometer with Suction Cup : Aquarium Thermometers : Pet Supplies
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