Fluctuating heater problems!

Hello! So we recently had a 100 watt heater for our 30 gallon tank and decided 150 would make more sense as our 100 watt heater would fluctuate way too much. However, with this new heater (aquatop - same brand as before), we’re still seeing a fluctuation. I just bought a second thermometer online in case that’s the problem but it doesn’t arrive until tomorrow. I’m just trying to get my tank up to 80 F...I was told this brand is great at not fluctuating so I’m not sure what the deal is. The red line on the heater is currently at the top of 82 F (see photo). Any thoughts? Or has anyone else had these issues? Thanks so much for your thoughts/advice!

 

How many degrees is it fluctuating by? And what is the temp according to the thermometer?

 

The old one would fluctuate from 75-80F. With this one, the light has turned off several times, which to my understanding means it’s at the expected temp, but it’s still in the 78s as opposed to 82. The thermostat isn’t exact if you’re familiar with the model/as you can see in the photo.

 

How high does the heater go on the temp dial? I’ve had similar problems before and just turned it up more until it went to the actual temperature I wanted
In theory: if 82 actually heats to 78, 84-86 would heat to 80-82

 

Good idea! I’m just hoping having two thermometers will help me guage it better!

 

I had a 100w that was preset to 78 and it would constantly stay at 74. Got an adjustable 200w and turned it up to 80.. got the temp reading 78. Just need to turn the heater up since they're not really accurate sometimes.

 

I had a 100w that was preset to 78 and it would constantly stay at 74. Got an adjustable 200w and turned it up to 80.. got the temp reading 78. Just need to turn the heater up since they're not really accurate sometimes.

Very good to know! Is it consistent now that you’ve figured out the real temps? Feel like I’m constantly paranoid and checking my thermometer!

 

Very good to know! Is it consistent now that you’ve figured out the real temps? Feel like I’m constantly paranoid and checking my thermometer!

Yes it is consistent now. So was I since I am still a really new fish keeper. Just remember the fish are there for you to enjoy and feel relaxed.. not something you should be constantly worried about! Just slowly turn the heater up until your temperature stays constant.

 

Yes it is consistent now. So was I since I am still a really new fish keeper. Just remember the fish are there for you to enjoy and feel relaxed.. not something you should be constantly worried about! Just slowly turn the heater up until your temperature stays constant.

Ha! So true - I should keep reminding myself that! Thanks again

 

You don’t want temp fluctuations but the temp dial being off a few degrees is normal.
if you want a good heater you can calibrate get yourself an ehiem jagr heater. Best there is IMO. My tanks always at 74.3F every time I walk by it. My other one is at 78 every time I walk by it.
you can also check thermometers by placing them in a ice fill cup with a bit of water and they should read 32 boiling water should read 212.

 

You don’t want temp fluctuations but the temp dial being off a few degrees is normal.
if you want a good heater you can calibrate get yourself an ehiem jagr heater. Best there is IMO. My tanks always at 74.3F every time I walk by it. My other one is at 78 every time I walk by it.
you can also check thermometers by placing them in a ice fill cup with a bit of water and they should read 32 boiling water should read 212.

Great idea! Thanks so much!

 

You can always use a heater controller. They have their own thermostat and a programmable digital display. Just plug the heater into the controller and let the controller turn the heater on and off. They are great for controlling multiple heaters! I plan to use one on my next build. The thermostat will be in the tank while the heaters will be in the sump.

 

That sounds like a perfect solution! Do you use a specific brand you recommend?

 

That sounds like a perfect solution! Do you use a specific brand you recommend?

I just bought an Inkbird from Amazon. It was $30. Make sure you get the temperature probe specifically for aquarium use.