EheimJager Aquarium Thermostat Heater 100W ( Pack of 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.

I've had good luck with name brand pet store heaters over the years but I just bought Discus which are very expensive and "delicate". I didn't want to take the chance on the heater already in the tank as Discus need consistent warmer temps & the old heater is one of those preset ones with no ability to increase temps if needed. My house isn't heated so with winter coming on and night temps already in the lower 50s I wasn't going to take a chance on losing my new high priced fish. EHEIM is a well respected German aquarium product manufacturer and the reviews on this heater were excellent. The instructions are in more languages than I bothered to count which tells you this company is used world wide by aquarists. Some reviews mentioned temp setting dial not being accurate but I monitored mine continually for 2 days with multiple thermometers to be sure it was the temp I set it for with no issues. I only bumped the temp up a few degrees from what it was with the old heater but the fish demonstrated that those few degrees were exactly what they needed. Excellent color & activity in their new home including good appetites which can be an issue with Discus.

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 great. Very reliable and still going strong months later

The media could not be loaded. I'm so glad I bought this heater! I needed to be able to raise the temp in my tank and this heater did it perfectly.

Bought this for my turtle tank. I have purchased several others and they did not work, this one seems to be holding up very well.

Shipped fast and was just as described. I have a 20gl High tank and the other heater I have was just to small(length wise) to keep the water at the correct temp. The bottom area of my tank kept dropping no matter where/how I placed it. With this heaters length I've been able to maintain temp throughout the tank without issues. Calibration was alittle off at first but easy to adjust with the included instructions.

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.