Heater temperature not correct!

[Dutch]

Hi all,

I have an internal heater in my 90p aquarium. It’s an Oase Pro Heater 300W should be good to heat 125-200 liter. My aim is to get the temperature at 24 degrees Celsius. So I’ve set the temperature at 24.

I recently checked the temperature with a thermometer and noticed it was only 21 degrees Celsius. I can offcourse set the temperature and the heater at 27 to get the overall temperature at 24. But I’m curious if more people experienced the same thing with internal heaters not actually delivering the temperature you set it on. And how others deal with this situation?!

I’ve added pictures of the heater, the temperature, and its position.

Thanks for your time!

 

[Maf 2500]

Aquarium heaters are not always that well calibrated out of the box so that is one possible reason. Some of the Oase heaters have a re-calibration system but yours looks different so not sure if that is an option.

Also, what is the ambient temperature in the room? If it is a long way below your set temperature (say 10 degrees or more) the heater may struggle to supply enough watts of energy.

 

[Bradders]

Also, when you measure the temperature in different areas of the aquarium, does it get closer to 24 near the heater and closer to 21 away from the heater? If so, it may be a flow issue.

Regardless, as @Maf 2500 says, I have 4 Oase heaters and some are spot on, and some have a 2 degrees difference!

 

[Dutch]

No , defenitly not accurate! Off +/- 5 degrees Celsius. Can’t calibrate so will do some tests with measuring the temperature at a few spots and than slowly increase it to 23-24 degrees.

Also, what is the ambient temperature in the room? If it is a long way below your set temperature (say 10 degrees or more) the heater may struggle to supply enough watts of energy.

The temperature is 19 degrees in house , so that can’t be the issue.. offcourse something to check with the cooler days coming!

 

[Dutch]

Also, when you measure the temperature in different areas of the aquarium, does it get closer to 24 near the heater and closer to 21 away from the heater? If so, it may be a flow issue.

Regardless, as @Maf 2500 says, I have 4 Oase heaters and some are spot on, and some have a 2 degrees difference!

I know measured it directly next to the heater. Then it’s off 4-5 degrees. Placed the thermometer now at the opposite site.. curious what’s the difference! Will let you know

 

[Spartacus]

I have my filter set to 23c I have a Blau brand glass thermometer that reads 25c and a JBL version that reads 23c.

There isn’t much consistency I think they don’t make stuff like they used to 😊 Makes it tricky to work out what’s going on but I’m also hesitant to try and fix an issue I may not even have due to a dodgy thermometer.

 

[MrClockOff]

Hi, it’s always advisable to attach heater with angle for better heat distribution. Though I prefer my heater being vertical too. Easier to hide. I have one Oase Heat Up 300w and it’s spot on. When set at 23 it does 23. But I also have another Oase Heat Up 150w and it’s of by 1 degree. When set to 23 it does 24.

 

[hypnogogia]

But I also have another Oase Heat Up 150w and it’s of by 1 degree. When set to 23 it does 24.

They can be calibrated.

 

[Dutch]

Hi, it’s always advisable to attach heater with angle for better heat distribution. Though I prefer my heater being vertical too. Easier to hide. I have one Oase Heat Up 300w and it’s spot on. When set at 23 it does 23. But I also have another Oase Heat Up 150w and it’s of by 1 degree. When set to 23 it does 24.

Maybe I will place it horizontal at the right. Not sure if will look nice but let’s give it a try in heat distribution.. although it seems the distribution is fine. It’s the same temperature at the other side of the tank (start measuring at different spots).

They can be calibrated.

Are you sure , also with the model I’ve got? See picture. Can’t find something on the box or internet.. not yet checked the heater itself.

 

[Bradders]

It’s the same temperature at the other side of the tank (start measuring at different spots).

So you must have a good enough flow to be the same all around the tank. I think its just not calibrated - assuming your other thermometer is correct!

 

[Maf 2500]

also with the model I’ve got?

The Oase Heat Up models can be calibrated - yours looks different... are you sure it is an Oase?

 

[bazz]

I have mentioned this a couple of times before on similar threads so I'll copy and paste, 'I've got three electronic thermostats and seven thermometers and all display different temperatures within a 2.5° range apart from the ADA glass thermometer which is a full 2° lower than all the rest, so I don't know'.

 

[dw1305]

Hi all,

'I've got three electronic thermostats and seven thermometers and all display different temperatures within a 2.5° range apart from the ADA glass thermometer which is a full 2° lower than all the rest

Old fashioned scientific <"spirit thermometers"> are the way forward.

A cheap product with one moving part, no electronics and good for all of eternity. In fact it might be a product for my <"luddite range of aquarium tat">.

cheers Darrel

 

[Dutch]

The Oase Heat Up models can be calibrated - yours looks different... are you sure it is an Oase?

Excuse me, it’s a “super fish heater” 300 watt. Just checked , those can’t be calibrated. Well, just going to increase the temperature till the

Old fashioned scientific <"spirit thermometers"> are the way forward

Old thermometer reaches somewhere around 24 degrees! Thanks!

 

[ScareCrow]

I think it's worth getting an additional temperature controller to plug the heater into. All heaters fail eventually and bimetallic strip heaters are more prone to failure by design.
I set the heater a few degrees above what I want, set the temp controller to what I want with the target, min and max. That way you get an alarm if it gets too hot/cold and your heater is regulated by its own thermostat and the temp controller.

 

[FrozenShivers]

I think it's worth getting an additional temperature controller to plug the heater into. All heaters fail eventually and bimetallic strip heaters are more prone to failure by design.
I set the heater a few degrees above what I want, set the temp controller to what I want with the target, min and max. That way you get an alarm if it gets too hot/cold and your heater is regulated by its own thermostat and the temp controller.

I run all my tanks with a temperature controller, usually easy to hide the probe behind plants or pipework. Also allows you to have more control over your heater, things like how many degree's the water temperature can fall until the heater kicks in so you can have say, a 3 degree window of heat. In addition to the benefits you listed.

Edit - I was in a setting menu by accident in the photo, my tank doesn't run at 2.7c

 

[LMuhlen]

Before doing anything drastic, I suggest getting a second thermometer to double check the temperature reading. I usually assume that thermostats are less precise in their calibration than thermometers, but thermometers are also usually all over the place as far as their offset. Especially those made for aquariums... When I go to a LFS and check the thermometers, they are all there side by side, each one showing a different temperature.