Why is my tank running so hot?

[gabray47]

I have a Hygger 100w adjustable heater. in a 20 gallon freshwater. I have it set to 75, but the temperature stays steady at 80 degrees. Right now I have 2 mystery snails and 2 nerite snails, but I plan on adding pygmy corys. Is this temperature too hot for them? Is it okay that the tank stays pretty steady at that temp, or does that mean the heater it is not working properly?

 

[Seasoldier]

Hi, pygmies like temperatures between 72 - 79 degrees so you're at the top end of their comfort zone, try turning the heater down a notch & see if that will drop the water temperature if not you likely have a malfunctioning heater.

 

[gabray47]

I have the heater set at 75. I turned it way down to 68 to see what happens. I have a second thermometer in there and the temp is about the same as the thermometer that came with the heater.

 

[Seasoldier]

I have the heater set at 75.

Yes, but you said the tank is running at 80 so if you drop the heater control down a notch or even two & the temp stays at 80 you'll know you have a duff heater & if that's the case I personally would replace it.

 

[gabray47]

Yes, but you said the tank is running at 80 so if you drop the heater control down a notch or even two & the temp stays at 80 you'll know you have a duff heater & if that's the case I personally would replace it.

Yes, I understand. I put it at 68 to see how it responds.

Yes, I understand. I put it at 68 to see how it responds.

Thanks very much! I'm doing what you suggested.

 

[Seasoldier]

Just one other thought that might make a difference, what's the ambient temperature of the room your tank is in?

 

[MrMuggles]

The lights and the filter can both potentially heat the tank. Does the heater have an indicator light to show when it’s heating?