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★ Featured in Atlantis

EHEIM

50W Heater

Name: EHEIM 50W Heater
Brand: EHEIM

Temperature Control · Heaters

Used on cool-season nights only.

Power

50 W (AC)

Tank range

up to 60 L (16 US gal) as primary heat

Temp range

18-32°C (adjustable dial)

Length

180 mm (glass tube)

Cable

1.7 m

See it in the Atlantis tank build →

50W Heater

$25.46 at Bulk Reef Supply

Buy →

Summary

EHEIM's compact submersible heater — the go-to for nano + medium tanks where you want reliable thermostat control without the cost of a Cobalt or Finnex Titanium. 50W rating suits ~60-100L; uses a glass tube + bi-metallic thermostat. Atlantis runs one as cool-season backup behind the chiller, not as primary heat.

Best for60-100 L (16-26 US gal) tank or sump supplement Mountsubmersible vertical Skill beginner

Tank-size fit (log scale)

50L 100L 200L 400L 800L 1500L

Best-fit range: 60-100 L

★ Atlantis verdict

"Cool-season-only at Atlantis — kicks in below 24.5°C as a chiller backup. Never been the primary heat source."

See it in the Atlantis tank build →

Heater anatomy

Submerged glass-tube heater with thermostat cutoff · keep at least 10cm below water line

Full specifications

Power 50 W (AC)

Tank range up to 60 L (16 US gal) as primary heat

Temp range 18-32°C (adjustable dial)

Length 180 mm (glass tube)

Cable 1.7 m

Indicator LED on top (ON = heating)

Thermostat Bi-metallic, ±1°C accuracy

Mount Vertical, fully submerged

Warranty 3 years (EHEIM EU)

What sells it / What holds it back

✓ Pros

✓ Reliable thermostat — EHEIM heaters rarely fail stuck-on (the dangerous failure mode)

✓ 3-year warranty (most cheap heaters are 1 year)

✓ Submersible — works in tank or sump

✓ Quiet — no buzzing on/off click

✗ Cons

✗ 50W is undersized for tanks larger than 100L without supplemental heat

✗ No digital display — analog dial only

✗ Glass tube CAN crack if dropped or thermal-shocked (don't run dry)

✗ Bi-metallic thermostat has ±1°C swing — fine for reef, tighter control needs a controller

What's in the box

Heater glass tube
Suction-cup mount bracket
Manual

Setup & dial-in

Step 1: NEVER run dry — submerge fully before plugging in. Glass cracks if heating element is exposed to air.

Step 2: Set dial to ~26°C, give it 20 min to stabilize.

Step 3: Verify with a known-good thermometer (your Apex temp probe is best). Adjust dial until indicator stays on the target.

Step 4: Wait 24 hours, re-verify. Bi-metallic thermostats drift slightly with break-in.

GOTCHA: If you ever unplug to clean the tank, wait 30 min before plugging back in (glass thermal-shocks at temperature deltas).

Maintenance schedule

monthly

Wipe salt creep off cable

every 6 months

Verify temp dial accuracy

every 6 months

Inspect glass for cracks

as needed

Replace if drift > ±2°C

Pairs with / Replaces

Pairs with

Featured in famous tanks

This piece of gear is in the documented build of 1 tank tour.

★ 60 gal

Project Atlantis

Atlantis Reef Keeping

LPS dominated

Where to buy

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