--- product_id: 50267179 title: "Eheim Jager Aquarium Thermostat Heater 100W (Pack of 1)" brand: "eheim" price: "$88.17" currency: USD in_stock: true reviews_count: 13 category: "Eheim" url: https://www.desertcart.us/products/50267179-eheim-jager-aquarium-thermostat-heater-100w-pack-of-1 store_origin: US region: United States of America --- # ±0.5°F TruTemp dial precision 100% fully submersible Auto shut-off dry-run protection Eheim Jager Aquarium Thermostat Heater 100W (Pack of 1) **Brand:** eheim **Price:** $88.17 **Availability:** ✅ In Stock ## Summary > 🔥 Keep your aquatic ecosystem perfectly cozy with pinpoint precision! 💧 ## Quick Answers - **What is this?** Eheim Jager Aquarium Thermostat Heater 100W (Pack of 1) by eheim - **How much does it cost?** $88.17 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/50267179-eheim-jager-aquarium-thermostat-heater-100w-pack-of-1) ## Best For - eheim enthusiasts ## Why This Product - Trusted eheim brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Precision Perfected:** TruTemp dial lets you recalibrate temperature within half a degree for flawless aquatic climate control. - • **Sleek & Submersible:** 100% waterproof design means it can be discreetly placed anywhere in your aquarium without worry. - • **Versatile Placement:** Calibratable thermostat compensates for any orientation—vertical, diagonal, or hidden behind plants. - • **Safety First, Always:** Automatic shut-off activates if water levels drop, protecting your tank and peace of mind. - • **Energy Efficient Heating:** Optimized 100W power delivers stable warmth, often outperforming higher wattage competitors. ## Overview The Eheim Jager 100W Aquarium Thermostat Heater is a fully submersible, precision-calibrated heater designed for tanks between 26-40 gallons. Featuring a TruTemp dial for ±0.5°F accuracy and an automatic shut-off safety mechanism to prevent dry running, it ensures stable, efficient heating. Its sleek red design fits discreetly in any aquarium setup, making it a trusted choice for millennial professionals seeking reliable, energy-efficient aquatic temperature control. ## Description Product Description All 9 EHEIM Heater models are 100% fully submersible and come with a new TruTemp dial that allows the user to recalibrate the heater within a +/- 0.5F degree accurancy for precise temperature readings. Safety Warning Please Read Instructions Before Use Review: Rock solid - 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. Review: It WORKS! - After a few time-consuming and tedious back-and-forths with heating, this is consistent and accurate keeps the temperature at the specified mark, is slim and discreet and never looked back after getting it. Not sure about the thickness as it has not broken but it is comfortable and safe to touch as a working heater should be. Would recommend. ## Features - Fully submersible - Thermo safey control protects against running dry - Will automatically turn off when water level dips too low - TruTemp dial recalibrates the heater for precise temperature regulation - International products have separate terms, are sold from abroad and may differ from local products, including fit, age ratings, and language of product, labeling or instructions. ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B003SNU1I2 | | Allergen Information | Apple Free | | Batteries Included | No | | Batteries required | No | | Best Sellers Rank | 47,294 in Pet Supplies ( See Top 100 in Pet Supplies ) 122 in Aquarium Heaters | | Colour | RED | | Customer Reviews | 4.4 4.4 out of 5 stars (1,231) | | Date First Available | 17 April 2012 | | Item Weight | 290 g | | Item model number | 3614090 | | Number of Items | 1 | | Pet Type | Fish and Aquatic | | Quantity | 1 | | Size | 26-40 US Gallons | | Specific Uses | Heating | ## Images ![Eheim Jager Aquarium Thermostat Heater 100W (Pack of 1) - Image 1](https://m.media-amazon.com/images/I/41-NtIUAmeL.jpg) ## Questions & Answers **Q: how do you calibrate this heater?** A: On top of the temperature dial it has a moveable dial. So for example it you've set temp to say twenty six but actually water temp is say twenty two then move secondary dial to twenty two then adjust from there. It's German engineering, very rarely wrong. **Q: Is this a UK plus product? because I ordered a similar one and they sent me a higher boly product with a us plug** A: Mine has a uk plug. Maybe send yours back. Definately the most reliable heater I have though. **Q: What is the length of heater** A: Its in my tank at the moment and nothing on the box to say how big it is but looks around 400mm/16inches to me. This is a great heater too **Q: What is the length of the cable?** A: Without disconnecting it and actually measuring the cable I would say that it is at least 1 metre long and probably nearer 1.25m. The top of my tank is 1.30 m off the floor and the heater is plugged into an extension lead inside a cupboard under the tank and there is a fair amount of slack cable. Hope that helps. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Rock solid *by G***L on 19 August 2016* 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. ### ⭐⭐⭐⭐⭐ It WORKS! *by G***. on 4 March 2021* After a few time-consuming and tedious back-and-forths with heating, this is consistent and accurate keeps the temperature at the specified mark, is slim and discreet and never looked back after getting it. Not sure about the thickness as it has not broken but it is comfortable and safe to touch as a working heater should be. Would recommend. ### ⭐⭐⭐⭐⭐ Eheim Great Heater *by A***R on 10 February 2016* So far so good. I had to calibrate slightly (which is easy to do). The eheim heater is now heating my aquarium to a nice steady 26°C which I am very pleased about. I previously owned a Deltatherm Aquarium Heater which suffered from internal condensation and would make loud clicking noises during and after heating, it also had a fluctuation of about 2°C, so within a 3 hour window it would go from 26°C to a reading of 24°C then back to 26°C ## Frequently Bought Together - EHEIM Jager Aquarium Thermostat Heater 100W ( Pack of 1) - Inkbird Freshwater Saltwater Aquarium Heater with Probe Thermostat and Thermometer Tropical Fish/Ornamental Shrimp/Reef Tanks 24 Hours Double Time with Day Night Automatic Temperature Controller - PAIZOO Fish Tank Digital Thermometer Accurate LED Display to ±0.9°F Tank Thermometer Aquarium Temperature Measurement Suitable for Fish, Axolotl, Turtle or Aquatic --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.us/products/50267179-eheim-jager-aquarium-thermostat-heater-100w-pack-of-1](https://www.desertcart.us/products/50267179-eheim-jager-aquarium-thermostat-heater-100w-pack-of-1) --- *Product available on Desertcart United States of America* *Store origin: US* *Last updated: 2026-07-08*