EHEIM Jager Heater 300 Watt

The rod for a comfortable climate.

EHEIM precision aquarium heater the legendary heater with modern technology and the latest features. Very precise, very easy to use and guaranteed highest quality and safety levels.

With the EHEIM precision heater your fish receive exactly the right temperature in any aquarium.

Obvious ideas often are the best ones. For example, the aquarium heater as a rod. The heating rod is simply hung in the water and heats it. It is true that the principle is still the same as decades ago. But a lot has changed in the meantime. And today the EHEIM adjustable heater is an ultra-modern electronic thermal device with the best available technology. A jacket made from special laboratory glass increases the heating surface, serves as a heat shield and ensures optimum even heat emission. And no matter if you want to heat a 50 or a 1000 litre aquarium you have 9 sizes to choose from.

Benefits of the EHEIM JAGER thermostatic heaters

Specifications

• Power: 300 W
• Aquarium volume: 600 to 1000 litres, per EHEIM’s own sizing
• Length: approximately 505 mm (20 in), 36 mm diameter
• Temperature range: 18 to 34 °C (65 to 93 °F)
• Accuracy: ±0.5 °C
• Glass: laboratory-grade, shatterproof, resistant to chemical and biological attack
• Safety: Thermo Safety Control, automatic shut-off if run dry

What’s in the Box

Heater with its integrated thermostat and indicator lamp, mounting bracket with suction cups, and the manual.

Setup & Use

Mount it fully submerged, at an angle or horizontally low in the tank, in a spot with flow past it: a heater in dead water heats a small pocket and the thermostat switches off before the tank is up to temperature. Leave it 30 minutes to equalise before setting the dial.

Set the dial to target, then check against a separate thermometer after a few hours. The TruTemp dial can be recalibrated to match your thermometer, which is what it is for: do that once rather than chasing the setting.

The indicator lamp shows when it is drawing power. A lamp that never goes off means the heater is undersized or the room is too cold; one that never comes on means the tank is already above the set point.

Compatibility

Freshwater and marine. At 300 W this is the largest in the Jager range and is sized for 600 to 1000 litre aquariums: on anything much smaller it will overshoot between thermostat cycles. On a large tank, two smaller heaters are worth considering over one big one: it halves what a stuck thermostat can do.

Safety & Precautions

Always unplug the heater before a water change, and leave it unplugged until it is fully submerged again. Thermo Safety Control will shut it down if it runs dry, but the glass still does not appreciate the thermal shock of cold water on a hot tube.

Use an earthed socket and leave a drip loop in the lead. Do not lift a hot heater out of the water. Check the seal and the dial position every few months: a heater failing on is the single most destructive equipment fault in the hobby, which is the argument for a separate temperature alarm on a valuable tank.

Returns & Replacement

Returns are accepted within 7 days of delivery, provided the item is unused and in its original packaging. Manufacturer-sealed items cannot be returned once the seal is broken, and sale-priced items are not refundable.

If your item arrives defective or damaged, message us on WhatsApp with your order number, or email us if you would rather, and we will replace it. Approved replacements are delivered within 3 to 5 business days. Transit damage is covered by insurance on every shipment. If tracking shows delivered but nothing reached you, tell us within 48 hours, which is the reporting window Indian couriers allow. Damage caused during installation or use is not covered; replacement spares for such cases are chargeable.

Full terms are on our Cancellation & Returns page.

Warranty & Support

This product carries a 3-year manufacturer warranty from the date of purchase, covering material and manufacturing defects. EHEIM excludes wear parts (impeller, sealing rings, hoses and filter media), along with glass damage, units that have been opened, and any unit fitted with non-EHEIM parts.

Warranty support is handled by us directly. Message our WhatsApp support with your order number and we will diagnose the fault first. Most cases are solved by replacing a single part, so you rarely need to send the whole unit. If the item does need to come back, it ships to our Delhi or Pune warehouse, whichever one served your order, and courier cost in both directions is borne by the customer. Your GST invoice is valid proof of purchase for the claim.