EHEIM Jager Aquarium Thermostat Heater 100W ( Pack of 1)

A must have for your aquarium. Works great but must clean your heater every month.

I used to use a different brand, I think it was Tetra but their heaters got bought by a different company. So I decided to go with this Eheim. Reason are is because it's just a simple heater. I didn't want a microprocessor controlled one because in my opinion, it's just more stuff that can break. The other reason was because a heater (once again in my opinion) is probably one of the (if not THE MOST) important accessory in your aquarium and should be something of good quality. I've had friends that went cheap on heater, and of course over time, they failed to the point where they were stuck in the heating position and cooked most of the things in their aquarium. Oh, and it was less on here than at the "P" stores. The Tru-Temp feature is pretty cool, so you can adjust the arrow to make the dial more accurate. I compared this heaters temp to a Fluke thermometer and it was .3F off from the factory position. Which for me is more than good enough. So yeah, I highly recommend this heater to anyone that wants a good heater.

The quality I expect from Eheim. Great heater! Thank you

Quality, dependable, consistent heating. German engineering gets it right again. Picked up another for a backup just in case and have a temperature alarm. 3 years strong. Only knock are the suction cups not holding as well over time on occasion.

I’ve been using cheap tetra heaters for a while but had to retire them, so figured I’d try Eheim. It’s ugly and I can see it shining through from behind the plants (it’s pretty thick foliage too), but right out of the box the temperature was spot on. It does fluctuate a bit at night and at the warmest part of the day, but it’s only by 0.2 to 0.4 degrees so I’m cool with that. Just know it’s gigantic and very shiny so it’s not for aesthetics. It’s a beast of a heater, more than twice the size of a 100W tetra heater. I will update this review when I have to replace it.

Works well with my 36 gallon. Glad I went with this one.

First one I received was heating so high above the set temperature that I maxed out the calibration adjustment and it still had to set it two degrees colder than the actual temperature (I had it set at 73 but the tank temp was at 75). I figured I'd just keep it like that, but then like 3 or 4 days later the temp suddenly started dropping, to the point where I needed to crank it up to 77 to keep my tank at 75. At that point I returned it for a new one. I've been using the new one now for about three or four days and it's working perfectly. Calibrated it the day I started using it and it has held the correct temp since then. Will update this review if anything changes. 12/24 - downgrading to 3 stars after using for a while. Yesterday I tried to bump the temp from 75 to 76 which seems like it should have been straightforward. Moved the dial 1 degree warmer but tank heated up to 77. So I dialed it back about 1/2 a degree and it stayed at 77 (heater was still kicking back on when temp was at 77. Then I moved it down again maybe 1/2 degree or so, and it then wanted to stay at 75. After fiddling for a while I think I finally have it stable at 76 -- with the dial reading 75. Seems like this should not be so hard. Halfway through all this I remembered the directions saying to unplug before adjusting the temp, so I started doing that -- but it didn't seem to make any difference. This thing has me stressed out. 6/24/22 - After 6 months of working perfectly to keep my tank at 78 degrees, today suddenly the temp is at 79 and holding steady there. I hate this thing. Downgrading from 3 stars to 1.

Product works great. it runs a few degrees warm in my tank (set to 75, reading 78). Its been going strong for over a year now. It was a lot longer than expected, and I had to put it in at a slant on my 40 gallon breeder.

Heater was delivered the day after I ordered it as expected. It comes well packaged and even has a plastic ring around the bottom of the tube to protect it in transit. I would have liked it if the cord was a bit longer. If you have your electrics hidden in a cabinet like I do, you need the cord to be able to go down the back of the tank, down the back of the cabinet and then into cabinet to where the extension socket is. If you don't have your aquarium right next to a socket, you are going to need an extension. Some people wonder why this heater 'needs' to be calibrated. I think that the truth is you don't really need to calibrate it, you could just set it to a reasonable temperature depending on your stock and then check the temperature with a thermometer for the first 24 hours or so, adjusting up or down as necessary. I think that the reason for the calibration wheel is that it enables you to set the exact temperature (in half degree increments) regardless of the ORIENTATION of the heater. Most people will hang their heater diagonally, the instructions for this one say to place it vertically but I have heard of people placing it horizontally as well (to hide it behind plants for instance). You can imagine that depending on orientation, the the thermostat might read the ambient water temperature slightly differently. The other thing that I like about this heater is that it seems to be a bit more efficient than others I've looked at. I used the 100w model to replace a 150w Fluval model that exploded as I removed it from the aquarium (never do a water change without turning off your heater first!) Looking at other models of heater, a 150w model was suggested for my 129 litre tank. In this range, the Jager 100w seems to be enough. Not sure how this is possible, but it seems to work fine. Perhaps the heater is cycling less and that can only be a good thing in terms of the stability of the water temperature and the longevity of the heater.

Awesome. That is all. Great product. Works well, temp is consistent (measure with digital thermometer). Best part thus far...if i forget to unplug when cleaning (water lowers) it senses low water and doesnt turn on. Will buy more in future (bigger tanks)

Living up to the company's reputation, the heater is efficient, durable and long-lasting. The holders, cord and instruction manual are also world class. There is a thermostat dial at the top, where you can set the temperature to a particular point. Note that you'll also need another thermometer separately to be sure of the accuracy. You'll need to adjust the settings per your second thermometer, which you can buy at affordable prices separately. One of the best features about such a high quality heater is that the temperature variation is very smooth, thereby not stressing out the poor fish. Important note - aquariums should NOT be set at a higher temperature (beyond 28-29C) because it raises the metabolism of the fish, thereby decreasing its life span. After a day or two of observation, I removed this heater because the city in which I live is usually warm. If I have an aquarium in Ooty or Bangalore, I might consider using this heater to maintain the temperature at around 27. If the surrounding temperature is beyond 27, you can turn this off.

Es de origen aleman no chino buena calidad

So far it’s working great I have waited for at least a month of continuous use before making a review and so far it’s good. It makes sense because it’s made from Germany. Should be a good quality. Also you should have at least a foot deep of water to use this because it has to be standing.