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

The Germans haven’t ever failed me when it comes to products they proudly announce to have designed. Works so good so far I wouldn’t buy anything else. Others have failed and this brand has not I have a heater from over ten years of this brand. Still works

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

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.

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.

Here's my experience:Put in in the tank, plugged it in, set it to like 78 and let it run for a day.The following day, I checked the temperature of the water on 2 separate devices and then calibrated the heater to the temperature I read on the 2 separate devices. So now, theoretically, the heater should be calibrated and good to go. Nope. I did 2 more rounds of this before the temperature on the heater and the temperature of the water matched.After that I didn't have any issues until I had to treat my tank for ick. I raised the temperature to 81 degrees no problem. It's when I had to go back down that I had all the issues. I set it back to 78, but the water only dropped to maybe 80. So I set it lower. This went on and on, just guessing at what temperature I was setting. After quite a lot of fussing with it, I finally got my tank back down to 78, but you can't calibrate the device as the indicator will not twist that far. Sooo yea...I hate it. I bought it because it was highly rated/regarded. I liked that you could calibrate it, instead of the potential that the heater is always just off by a degree or 2. So while this thing technically still heats my tank, I just ordered a new heater from a different brand.

Like all aquarium heaters . You get good ones and bad ones. So far so good . Replacing a 3 year old one. Do have it hooked to a inkbird for more safety. Would buy again.