i have a betta in a one gallon tank

  • We are currently upgrading MFK. thanks! -neo
The tank is too small unfortunately. I'd keep one in a 2.5g minimum. Better yet, a 5g and you can fit the heater there better.
 
a 2.5 or 5 gallon tank would be better for the betta and the heater would work properly as well
 
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