Can A Fish Tank Filter Catch Fire?

New tank owners quickly understand they should leave their aquarium filter running all the time. However, they may worry there can be issues with something electrical running all the time around water for the uninitiated.

It raises many questions and one of the most concerning being.

Can a fish tank filter catch fire? It is possible for fish tank filters to catch fire, and those that do are often cheaply made with poor wiring. However, there are a couple of other reasons, such as filter motor burn out, cord/ plug damage, lack of cooling, sticking brushless motors, that cause filters to heat and fail.

Will Fish Die if I Turn Off My Aquarium Filter?

It is possible for fish to live with the filter turned off for minimal periods. However, these periods are far shorter than if you think you can turn off your filter each night before fires start.

Filters do much more than catch any debris, and inside there are communities of beneficial bacteria.

Should you turn off your filter each night, you could see an impact on your fish’s health because the bacteria are dying. Should these bacteria die, then you can have many issues with your fish.

Reasons for Aquarium Filter Issues

Here are a couple of reasons why you could find your tank filter failing and leading to fire hazards.

Cheap Quality Filters

Purchasing an aquarium kit can lead to low-quality filters being supplied and used, or if you are buying second hand, there could be an issue you are unaware of.

If you have had an aquarium for a while, you may find the motor heats if there is a lack of sufficient lubrication, as can happen on some imported devices.

While it may not lead to a fire as such, it could heat the surrounding plastic areas enough for them to melt, or it causes your motor to seize and die.

Cord or Plug Damage

Since you need to leave your filter running all the time, cheap plugs or cords can be a point of failure. While a filter doesn’t use too much electricity, cheap thin cables can heat up, and the plastic casing can melt.

You’ll find this more of an issue should your cable be bunched up or sitting close to any carpet or fabric. Likewise, if there is a faulty connection in the plug, there could be the potential for sparks.

Lack of Cooling

You can find a couple of things here that lead to your filter not being cooled sufficiently. Water levels dropping too much would be the most obvious, and thus your filter motor can spin as freely as it wishes.

One of the more common reasons this occurs is with filter motors clogged with gunk or brushless motors. If your motor is clogged, these can be cleaned as part of your aquarium maintenance.

Brushless Motors Sticking

Power outages are the most significant causes of sticking motors for brushless designs. The way this work is through magnets pushing the motor. Should there be a power outage, the motor can settle between magnets.

If this happens, you’ll find that as electricity returns, it tries to push and pull the motor at the same time. If there is no greater force, then the motor sits in one position with the electricity flowing through it.

Should your motor be stuck between two poles, you could find it heats up considerably. It may not burst into flames, yet if the construction isn’t reliable, the heat could melt it, and then the motor wouldn’t be able to turn.

The fix for this may appear daunting, yet it is relatively simple. Open the rotor assembly and poke the rotor with the tip of a pen or other similar object. Make sure not to use your finger as there are electricity and water.

You should see your motor spin, and you can close it back up, and then there are no more issues.

If you are home, this is a quick fix; however, should it happen when you are not at home, your motor can sit for hours trying to spin and thus heating up.

Fish Tank Filter Not Working

If you think your filter isn’t working and could lead to a fire, there are three reasons for your filter not working.

Here is a quick rundown of the top three aquarium filter problems.

Tank Filter Not Running

Clogged motors, as we have seen, can be a crucial issue. However, a clogged impeller intake or outtake can cause much the same problems. Should this happen, your filter will sit there, making noise without carrying out any function.

The solution for this is as you would do as part of your aquarium maintenance. Open up your filter and take it apart so you can remove whatever is causing the clog.

You may need to force water through the motor or use compressed air to free any stubborn clogs.

Lack of Suction

You will find this is one of the primary reasons for filters not working, and getting hot. The motor drives the impellers that create the suction. The overall function here is for the impellers to suck water via the intake valve, through the filter media, and exit into the tank with clean water.

Again, this is a straightforward fix, and you will need to take this apart as you would if you were freeing the motor after a power outage. If you see a visible clog, you can release this quickly. If it is built up gunk, you can wash it quickly under running water from your faucet.

Sand substrates can make matters worse, as these can bunch quicker. Small pebbles can have a similar negative impact.

Incorrect Flow Rates

While not an issue with your filter that can cause failure or fire, it can significantly affect your fish’s health.

Different fish require different flow rates. Some are better with a gentle flow, where others prefer a faster flow rate.

It requires you to purchase the right filter, and you can often find the one that comes as part of your kit may not be a variable rate filter.

An overpowered won’t affect tank performance, yet the more significant concern is when your filter is underpowered. If you have an underpowered filter on a larger tank, there can be far more debris, and thus it clogs much faster. Weaker filters will also affect the health of your fish more quickly than a more powerful filter would.

The solution here is to make sure you purchase a filter suitable for your tank, and to safeguard your fish, be sure to buy a variable flow rate filter.


You should find little reason for a good tank filter to cause a fire. More fires are caused by sockets being overloaded, and the incorrect fuse size is used.

While this isn’t an issue with the filter, we saw cords and plugs can heat up and melt if the make isn’t reliable. Should this happen, bare wires can be exposed and then cause a short.

It is much safer to consider a filter upgrade and make sure it is rated for electricity and your tank. Besides this, you can get an additional breaker to sit between your socket and filter plug, or you can find these built into an extension cable.

If there is such a surge or short, these would trip and cut power to anything connected. It may not help your fish, yet it could prevent anything worse from happening in your home.