![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
![HYDROTOOLS BY SWIMLINE Cool Shark Soft Top Thermometer Large Floating Easy Read For Water Temperature Shatter Resistant With String For Outdoor And Indoor Swimming Pools Spas Ponds Bathtubs - Walmart.com HYDROTOOLS BY SWIMLINE Cool Shark Soft Top Thermometer Large Floating Easy Read For Water Temperature Shatter Resistant With String For Outdoor And Indoor Swimming Pools Spas Ponds Bathtubs - Walmart.com](https://i5.walmartimages.com/asr/3be478eb-a7f9-421e-94ae-eb802a48a310_1.d9da3607f4956f9451b6e396fab3f30e.jpeg?odnHeight=768&odnWidth=768&odnBg=FFFFFF)
HYDROTOOLS BY SWIMLINE Cool Shark Soft Top Thermometer Large Floating Easy Read For Water Temperature Shatter Resistant With String For Outdoor And Indoor Swimming Pools Spas Ponds Bathtubs - Walmart.com
![Amazon.com : PENN-PLAX Therma-Temp Floating Aquarium Thermometer – Mercury Free – Safe for Freshwater and Saltwater Fish : Pet Supplies Amazon.com : PENN-PLAX Therma-Temp Floating Aquarium Thermometer – Mercury Free – Safe for Freshwater and Saltwater Fish : Pet Supplies](https://m.media-amazon.com/images/I/616q8s5Nh2L._AC_UF1000,1000_QL80_.jpg)