Heater for 100g ish aquarium

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Rafini

Piranha
MFK Member
Jun 28, 2012
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Calgary, Canada
I have a 120g that is pre-drilled and has an overflow that isn't hooked up. naturally my water level is dropped by about 1-2" so I would say closer to 100g in operating volume.

I currently have an Eheim Jäger 300w that has worked great for the last 8 years or so. It was operating too high about a month ago, so I reduced it down to a lower level and now after turning it back up a little higher it appears to be broken.

for the last day, the light has been on constantly yet the temperature of the aquarium hasn't increased by a single unit. It's essentially sitting at around 21 which is typical room temperature. you can grab the tube and its not even warm. Currently set in the 80s to quickly heat up the aquarium, yet the aquarium temp is around 70

Now i have to go and get another heater, can anyone recommend one that is relatively inexpensive?
 
I always thought Jager were top of the line heaters. Since this one lasted you 8 years why not get another one?
In the U.S a 300watt is only a bit over $30 which is relatively cheap when compared with it's contenders.

Do you want to try a different brand?
 
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There seems to be a lot of options on the market for heaters now, my last 300w which I got at the same time as this one got stuck on and roasted all my fish. This one however was good until now.

It's boxing week and my only option for finding a jäger now would be online.

I'm also thinking that 300w is a little too much? a lot of other brands are rated at 80g but the Jäger 250w is rated at 106-159 gallons. So I think I will downsize. The current 300w is 20" long and looks huge in the 4x2x2 aquarium.

I was considering running out to the store and getting a cheap replacement, thats why I asked about recommendations but I suppose Eheim Jäger line has an excellent reputation.

Its just I find calibrating them very frustrating. The only countries on earth that use Fahrenheit are Belize and the US (and overseas territories). there is absolutely no Celsius print so I have to do conversions just to figure out the calibration and its a little annoying as Fahrenheit is almost never taught in schools.
 
There seems to be a lot of options on the market for heaters now, my last 300w which I got at the same time as this one got stuck on and roasted all my fish. This one however was good until now.

It's boxing week and my only option for finding a jäger now would be online.

I'm also thinking that 300w is a little too much? a lot of other brands are rated at 80g but the Jäger 250w is rated at 106-159 gallons. So I think I will downsize. The current 300w is 20" long and looks huge in the 4x2x2 aquarium.

I was considering running out to the store and getting a cheap replacement, thats why I asked about recommendations but I suppose Eheim Jäger line has an excellent reputation.

Its just I find calibrating them very frustrating. The only countries on earth that use Fahrenheit are Belize and the US (and overseas territories). there is absolutely no Celsius print so I have to do conversions just to figure out the calibration and its a little annoying as Fahrenheit is almost never taught in schools.

What conversions do you need? Tank is a little cool, turn the dial up, tank is hot, turn dial down. :)
 
Sounds simple enough right? I find myself having to recalibrate a lot and maybe thats cause it was on its way out.

So in the end I decided to go with an Eheim Jäger 250, The only store in town that had any eheims and this was their last one. It was also 25% off so I'm pretty happy.

Tank has already heated up to about 23 and still going so I guess I'd rather go with a product I know can last 8 years than take my chances with a cheaper model!
 
Maybe try 2x smaller jager heaters at either end of the tank to help lessen the load of one heater warming up the whole tank each time???
 
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Currently set in the 80s to quickly heat up the aquarium, yet the aquarium temp is around 70
Hello; I fear this is a common misconception about heaters. The adjustment knob does not adjust the power output of a heater. ( at least never has on any heaters I use). A 300 watt heater puts out 300 watts any time it is actually on. Set it at 75 degrees and when on will blast out 300 watts until the thermostat senses a temperature of 75 degrees. Set it at 80 degrees and it blasts out the same 300 watts of heating power until the temp reaches 80 degrees. The adjustment knob only sets the temperature at which the heater turns on and off, not the power output.

got stuck on and roasted all my fish.

try 2x smaller jager heaters
Hello; I really like this suggestion. I do follow this practice myself. There are two clear advantages. First is if one fails and is stuck ON then it's lower power is much less likely to "roast" the tank.
The other is if one fails and is stuck OFF then the other usually has enough power to keep the temp from falling too low real fast, thus keeping the tank going until a new one can be had.
 
I'm with the others about using 2 (or even 3) less powerful heaters.
The only time a heater has ever killed my fish, is when it failed in the "on" position, and cooked them. Most tropicals can take temp of a failed "off" heater into the 60s.
Since the time my fish were cooked, I don't use high wattage heaters, instead a few lower watt ones. If a small one fails in the "on" position, hopefully the thermostats of the others turn them off, and a smaller heater has less ability to overwhelm a 100 gallon tank.
 
Yeah, I usually suggest a pair of heaters, but I don't usually follow my own advice. Every time I go and see I can two Jagers 150 watt heaters for $84.90 each, $169.80 total. Or one 300 watt for $79.90. Yeah, nah, I'm getting the single heater.
 
my last 300w which I got at the same time as this one got stuck on and roasted all my fish.

only time a heater has ever killed my fish, is when it failed in the "on" position

I don't usually follow my own advice. Every time I go and see I can two Jagers 150 watt heaters for $84.90 each, $169.80 total. Or one 300 watt for $79.90. Yeah, nah, I'm getting the single heater.

Hello; Interesting point of view.
 
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