Heater Stick Too Hot For Betta Fish: What To Do?

thermometer inside planted aquarium

How would it feel to see your favorite pet fish getting boiled in the water? Not good, I guess. A ‘too-hot’ heater stick might not boil the water but make it hot enough to harm your Betta. But what will you do in such a case?

First of all, turn off the heater. You need to check then if you’ve set the temperature right. If that’s okay, check if there’s any fault in the thermostat. Get it repaired or replaced if required. After that, keep a thermometer to monitor the tank’s temperature regularly.

But how much hot is exactly too hot for Betta fish? And why would a heater stick go hot all of a sudden? And most importantly, what if the heater stick is not boiling the water? Well, I can’t give you an answer without your scrolling. So, let’s roll down.

Key Takeaways

  • The ideal temperature for a Betta fish tank is 78° to 80°F.
  • A heater with a malfunction, wrong setting, faults in the thermostat, and problem with heater calibration can overheat the tank.
  • Fixing the setting and thermostat issue and picking the heater of the right size can possibly reduce the overheating issue.
heater inside aquarium

How Hot Is Too Hot for Betta Fish?

You can’t stand a temperature beyond your range, can you? The same goes for Betta fish. But how much temperature is ideal for them? Well, you better stick to a number like 78° to 80°F. That’s the most comfortable one. You can also go a bit up and down.

See also  How To Cool Down Betta Fish Tank?

But if the water goes below 74°F, it’ll lead your fish to temperature shock and affect its health negatively. And if it goes above 86°F, it can boil up the water for the fish and can even kill it.

Why is the Heater Stick Getting Too Hot?

If the heater stick is acting weird suddenly and getting too hot, clearly, there’s a reason behind it. But usually, which ones pop up the most? Well, as far as my study says, it starts with –

Wrong Setting

It happens mostly with the newbies who don’t know the right temperature range for their fish. You need to understand that the temperature requirements for fish and humans are not the same. If the temperature crosses the 78° to 80°F range, it won’t be a pleasant place for your Betta.

Fault in Thermostat

Nobody said there couldn’t be a malfunction in the thermostat. If anything like that happens, the temperature might go beyond the one you’ve set and make the water too hot for the fish.

Problem with Heater Calibration

Don’t be surprised if your heater’s calibration issue messes up with the water temperature. It can happen for anything like regular wear and tear, drift in temperature sensors, manufacturing variations, etc. Any of these can easily lead to wrong temperature readings.

Wrong Heater Size

It’s a must to pick the right-sized heater for your tank. If you won’t, there’s a chance of occurrences like overheating. Usually, some fish enthusiasts get comparatively powerful heaters for their tanks, and that’s when the heater goes too high for the water.

Wrong Heater Placement

How perfectly you’re heating up the water depends a lot on where you’re putting the heater. You need to place it somewhere where it can distribute the heat evenly. But putting it too close to the substrate or the surface might create hotspots for the fish.

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After all, it’s a machine, too, right? So, malfunctioning is not impossible. With time, the heater starts to lose its ability to function properly, especially under some kind of damage, wear, and tear.

expert quote betta after years of keeping bettas, i can tell you it definitely gets easier and easier as time goes on

Lack of Enough Water Circulation

The tank’s water must circulate for even distribution of heat your heater emits. Otherwise, even heat distribution will be impossible; all you’ll have is a hot spot. This is where an aquarium pump comes in handy.

Fluctuation in Power

Every heater needs a certain amount of power to function correctly. So, excessive fluctuation in power can also influence the performance of your heater. It can even damage the heater once and for all.

Lack of Maintenance

Every machine needs maintenance, and the same goes for aquarium heaters. So, if your heater is acting weird and heating up the water too much, think about the last time you had it checked.

How to Fix the Hot Heater Stick Issue?

I always believed that –

“You can’t make the tank your Betta’s heaven while giving it the feeling of living in a hot desert.”

But every issue comes with a solution. So, if the issue is your hot heater stick boiling up the water, there are solutions for that as well, such as –

Checking the Temperature

Always start with the basics and check the temperature first. So, to be sure on that part, use a properly functional aquarium thermometer. If it’s going beyond the ideal range, which is 78° to 80°F or 25° to 27°C, check the heater and lower the heat manually. In case the heater is not responding, get it repaired or replaced.

Checking the Thermostat

Check the thermostat; you might see some damage or abnormalities there. If these damages mess with the heater’s ability to heat the water, replace it. But make sure you’re doing it all under the manufacturer’s instructions. Contact the manufacturer’s customer support if you’re confused with the instructions.

expert quote betta betta fish require a tropical temperature, ideally between 78 to 82 degrees Fahrenheit

Checking for Heater Mismatch

There’s a chance of you using the wrong heater. First of all, figure out what kind of heater is suitable for your tank size. Also, if you’re using the wrong one, ensure you get one with the right wattage. Otherwise, you might buy a more powerful heater that will boil the water.

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Waiting to Cool Down

If you don’t have the option to replace the heater right now, try letting the water cool down naturally. All you have to do is turn off the heater and wait for the temperature to come down.

Checking the Damage

Check if the heater is damaged somehow. It can be anything like cracks or frayed wires. If it’s fixable, repair it or simply replace it to cut the hassles.

my betta swimming

Making Water Circulation Better

Overheating might not always be your heater’s fault. If the water circulation is not on point, the water can still get too hot for your fish. Adjust the decorations or add a water pump to make it better.

Fixing Calibration Issue

A heater should be accurate when it comes to reading the water temperature. If that’s not happening lately, you need to get it fixed in the first place. To be sure on this, use a thermometer to double-check if there’s any calibration issue in the heater.

Fixing the Power Fluctuation

As I said, this one can also mess with the heater’s performance. So, make sure you’re using a surge protector here. This will help you to stabilize the power and protect your heater.

Before We Go….

Fixing your heater might solve the overheating issue. But what if there’s something else heating up your tank? And how will you cool it down if something like that happens frequently? Well, I’ve got some answers, but you’ll have to dive into my next blog – How To Cool Down Betta Fish Tank?

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Muntaseer Rahman

About Author

Hello, I’m Muntaseer Rahman, the owner of AcuarioPets.com. I’m passionate about aquarium pets like shrimps, snails, crabs, and crayfish. I’ve created this website to share my expertise and help you provide better care for these amazing pets.


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