Can My Heater Catch Fire?

Hi, I'm using a 50 watt heater on my 5.5 gallon tank and I'm wondering if it could potentially catch fire due to it being too big for the aquarium. The brand is not the best either. The reviews weren't great from what I remember. I bought it over a year ago and I've never had any issues with it. My 10 gallon tank's heater also doesn't have very good reviews but again, I've never had an issue with it. Does anyone think they could explode and catch fire?

 

That should be ok . What will happen is the heater will switch on and off as it should in any tank. However it will turn on and off more often meaning it will not last as long in terms of years.

I personally have used 200 watt heaters in small tanks of 80 litres/ 20 gallons or LESS for weeks at a time. While not ideal just because they are big and take up space. They are not a fire hazard.

You must have all of the heater under water all of the time. If that means placing the heater horizontally do it.

If you don’t have the heater below water at a water change it will explode/crack/ stop working very quickly.

We all need a spare heater. Ask the Easter bunny to get you one the correct size and keep the big heater as a spare.

 

No fire hazard there in my opinion. As long as you know its keeping the right temperature an it's not consistently on things should be fine. One piece of advice for future reference, Don't invest in fluval E range thermostat as a spare back up. 1, they're expensive.
2, they're very sensitive.
What I mean by sensitive is,they've got a low flow sensor.sounds good but every 3rd/4th water change I have to remove it to clean anything that settles on the sensors. The digital display is good but when it picks a temperature fluctuation ie. From water changes they flash different colours pending on to warm (red) to cold(blue) green normal.It can be a bit disconcerting until you get use to it.
Last issue is you NEVER know if its actually warming up the water.

 

I've been keeping fish for 40 or so years and the only time I have ever seen heater problems beyond "quit heating" was due to exposing the heater to air while it was still plugged in. Submerge the thing completely and it will do it's job.

Worst case if it did have a physical failure is that it would short out and pop your circuit breaker.

 

Ok. Thanks. Is it fine for there to be a bit of debris (fish poop, fish food, sand) and calcium on the heater? Will this cause a problem? And one other question: How far does the heater have to be submerged? One of the heaters has a minimum water level so I'm not worried about it but the other one doesn't. The heater itself is entirely submerged but only about an inch of the cord is submerged. Will this be fine?
One last question: When the 50 watt heater in the 5.5 gallon tank fails, what will happen? Will it just stop heating?

 

Answer to your last question is yes.it will stop heating. If you submerge any heater just leave the top 25ml above the water line that should be fine.As for any debris just clean it off.

 

Answer to your last question is yes.it will stop heating. If you submerge any heater just leave the top 25ml above the water line that should be fine.As for any debris just clean it off.

By "leave the top 25ml above the water" do you mean the water level or the heater? Will the debris cause problems if I leave it on the heater though?
EDIT: There's also a calcium/limescale built up on both of the heaters.

That should be ok . What will happen is the heater will switch on and off as it should in any tank. However it will turn on and off more often meaning it will not last as long in terms of years.

I personally have used 200 watt heaters in small tanks of 80 litres/ 20 gallons or LESS for weeks at a time. While not ideal just because they are big and take up space. They are not a fire hazard.

You must have all of the heater under water all of the time. If that means placing the heater horizontally do it.

If you don’t have the heater below water at a water change it will explode/crack/ stop working very quickly.

We all need a spare heater. Ask the Easter bunny to get you one the correct size and keep the big heater as a spare.

The heater only heats the 5.5 gallon to about 77 degrees when it's meant to heat it to 78 degrees. I've had it a bit over a year, I think. Is it already deteriorating? And if I can't get a 25 watt heater right away (might be a few months before I could get one), will the 50 watt be okay? Thanks.

 

By "leave the top 25ml above the water" do you mean the water level or the heater? Will the debris cause problems if I leave it on the heater though?
EDIT: There's also a calcium/limescale built up on both of the heaters.

The heater only heats the 5.5 gallon to about 77 degrees when it's meant to heat it to 78 degrees. I've had it a bit over a year, I think. Is it already deteriorating? And if I can't get a 25 watt heater right away (might be a few months before I could get one), will the 50 watt be okay? Thanks.

Leave the top 25ml stick out the top of the water just so you can adjust the temperature if needed. If the timescale is bothering you remove the thermostat let it cool down then use some white vinegar and rough faced scourer then rinse off under water and put back in the aquarium.

 

With any tanks that I use with heaters I put all the heater under water. I have them horizontal below the level of a water change. The heater instructions probably say to turn the heater power off anytime you put your hands in the tank water. Following the instructions never killed anyone?

The line at the top of the heater is the minimum level. .Once in a tank you should not need to change the temperature all year round? If you do you get your hands wet that’s all.

 

If you submerge any heater just leave the top 25ml above the water line that should be fine.

Bad idea to give this as a general advice, there are models that have to be fully submerged. Many manufacturers (I know it from Eheim and Juwel, just to name examples) have a minimum waterline marker on their heaters. And for these I can tell you your advice would in many cases render the warranty null and void. Any problems or accidents are on the user.

 

If the timescale is bothering you remove the thermostat let it cool down then use some white vinegar and rough faced scourer then rinse off under water and put back in the aquarium.

Okay. Could the limescale/debris be a fire hazard though?

 

Could the limescale/debris be a fire hazard though?

No. Just a hazard to the rubber seal over time. Clean it once in a while. Done.
The only firehazard around a tank comes from water possibly getting into the power outlet/connector strip, causing sparks setting stuff AROUND the tank on fire. Make sure powerlines have a sling downward before going into the outlet so any water just drips to the floor and not into the outlet.

Inside the tank there is nothing that can cause a fire.

 

No. Just a hazard to the rubber seal over time. Clean it once in a while. Done.
The only firehazard around a tank comes from water possibly getting into the power outlet/connector strip, causing sparks setting stuff AROUND the tank on fire. Make sure powerlines have a sling downward before going into the outlet so any water just drips to the floor and not into the outlet.

Inside the tank there is nothing that can cause a fire.

Oh, okay. I was under the impression that I had to clean the limescale/debris off like every day or something. Forgive me for being stupid, but what exactly to you mean by rubber seal? The seal on the heater holding it together? Or something else?
Thanks for the advice/tips by the way!

 

Forgive me for being stupid, but what exactly to you mean by rubber seal? The seal on the heater holding it together? Or something else?

At the point where the heater and the powerline connect there's a seal keeping water out of the heater. Limescale can damage this seal over time. But this takes years. Just clean it once every few months or so.

 

I have mine with all the glass and part of the plastic submerged, as long as the glass is under, you’re OK. Scaling reduces the heat transfer efficiency, should be cleaned when it becomes significant, when it’s crusty, a couple months or so, I would think. I’ve never had any scale on mine. In 30 some years of fish, I had one heater stop working and one other that would keep heating, thermostat wouldn’t shut off.

 

At the point where the heater and the powerline connect there's a seal keeping water out of the heater. Limescale can damage this seal over time. But this takes years. Just clean it once every few months or so.

Okay. Thanks!

 

Don't worry, if it starts on fire the water will put it out.

 

Normally a five gallon tank requires somewhere between 25-50 watts depending upon the difference between room temperature and tank temperature. Thus, a 50 watt heater is not significantly oversized.

It is best not to run a heater that is obviously oversized for a tank (such as 150 watts for a 5 gallon tank) as it is possible for thermostats to fail in the on position. If that happens with an oversized heater, the tank temperature can become high enough to harm the fish. In most instances, however, heaters will fail in the off position and tanks will become too cold.

Because electricity and water are not a good combination, I always recommend that you use a ground fault circuit interrupter (GFCI) on the outlet into which the heater is plugged. That way, if water leaks into the heater, the breaker will trip rather than causing a potential shock hazard.

It would be unusual for an aquarium heater to generate a fire hazard unless there is damage to the electrical cord, or the circuit is overloaded.