Heaters and Temperature Setup for a Reef Aquarium - Don't Learn The Hard Way!

Categories: Heaters & Chillers, 5 Minute Saltwater Aquarium Guide

Last updated: Jun 29, 2022

Heaters have one of the unique positions in our hobby as being one of the most inexpensive and easy to install components of your tank’s life support system but are also the number one cause of equipment-related failures. With that conundrum, it is all that more important to get it right the first time and arm yourself with the knowledge to avoid those mistakes.

Using reliable equipment is equally as important as taking the right approach to water temperature control and being proactive about heater replacements and maintenance. These easy-to-follow steps will ensure you are making the right choices and doing everything you possibly can to avoid heater-related catastrophe.

#1 Heater Selection

There are dozens of different heaters on the market and for the first year of keeping your tank, there really isn’t going to be much of a performance difference between most of them. Use whatever heater you feel comfortable with. Set your budget and look to the customer reviews which are a great resource because there really is a ton of options, all of which do the same thing. Be sure you measure the available space you have to install the heater too because it must stay submerged at all times.

Choose a heater capable of providing 3 - 5 watts of heating power per gallon of aquarium water.

If you live in a cold climate, always size heaters based on the higher end of the wattage range. Using two heaters is a popular approach too, especially on larger aquariums or aquariums located in cold climates where the heater will have to work hard to maintain warm tropical water temperatures. Choose one full-size heater as your primary heating element with a second heater on stand-by (set to a slightly lower water temperature) that will kick in should the main heater fail.

Understand that heaters will need to be replaced on a regular basis too. Heater relays and internal components simply wear out over time and the best approach to avoiding a heater-related catastrophe is to proactively replace your heater and/or heater controller on a regular cycle. Every 1-2 years in most cases depending on the particular heater you are using.

Eheim Jager Heater

Classic glass and plastic heaters with built-in thermostats have long been the most affordable option for aquarium owners. The Eheim Jager is the #1 choice in this category because they are relatively reliable and allow the user to calibrate the temperature controller.

Titanium heaters are typically the most expensive option because they are made of higher-quality materials (longer-lasting), are more compact, and require the use of a separate temperature controller. Having a separate temperature controller gives you the flexibility to replace only the element or only the controller, whichever need comes first. You can also find features like a replaceable temperature probe, Wifi capabilities for remote notifications, more robust relay switches, and dual sockets for running multiple heating elements.

We created the BRS Titanium Aquarium Heater System to be the best aquarium heating system on the market. The German-made BRS titanium elements are manufactured by Schego using high-quality materials and strict quality control guidelines. We recommend pairing the BRS elements with the Helio PTC Smart Controller or Ink Bird Wifi Temperature controller but you can also plug them directly into your Neptune Systems Apex or GHL Profilux Controller.

BRS Titanium Aquarium Heater System Features:

Shatterproof & Robust Titanium Heating Element
Fully Submersible Elements
Simple Suction Cup Mounting System
6-foot power cord
3-Year Heater Element Warranty

#2 Heater Installation

When you install an aquarium heater, make sure to put it somewhere where it will always be submerged, even when the pumps are turned off for maintenance or feeding. A heater out of water can be a dangerous fire hazard and will quickly malfunction. Secure the element using a heater holder to your sump, in the main display, or in the filter chambers.

Before plugging in your heater for the first time, submerge the heating element into the water and allow it to acclimate for 30 minutes before plugging it in. This allows the heating element (especially glass) to equalize with the water temperature before it starts heating up. Otherwise, the glass could break because of the temperature swings.

Mount your temperature controller in a convenient location, away from moisture, where it is easy to see the LCD display and access the settings. If your controller has a separate thermometer, it is best to submerge the thermometer into your display aquarium because this is where the water temperature matters most. Even if your heating element is in the sump, the thermometer should be reading the temperature in the display.

#3 Heater Operation

The general target temperature for a reef tank is 75°-78° Fahrenheit. You will want to have a separate thermometer on hand to ensure the heater is working and configured properly. After mounting your heating element and controller, you should configure the controller. The exact configuration process will depend on the particular heater you have and the available features. Follow the manufacturer instructions or just give us a call if you run into trouble.

Configure the display to either Fahrenheit or Celsius
Calibrate the thermometer (if applicable)
Set the desired tank water temperature
Set on/off cycle variance (if applicable)

Take an initial water temperature reading before the heater turns on. During the first 24-48 hours, monitor the water temperature closely using a separate thermometer. Should the heater overheat or under-heat, adjust the controller settings right away and give the heater time to accommodate the new settings. Monitor to ensure the heating element is switching on at the appropriate time and switching off when the water has reached the set temperature.

How To Avoid Heater Catastrophe

Every electrical component on the tank is going to eventually wear out or break and you want to have a plan. Being proactive and replacing your heater before it breaks is going to avoid some serious headaches. Even just a few hours in cold/hot water can wipe out your tank.

If you are using an inexpensive $30-$40 heater, just replace it annually.
If you are using something like the BRS heaters that use a higher quality long-lasting heating element coupled with an external controller, simply replace the broken component every 1-3 years. This is most often going to be the controller. The controller and relays are what fail the fastest and cause the heater to stick in the ON position.
In the event of a problem, check the temperature calibration and accuracy of the temperature probe or built-in thermometer.
Monitor water temperature closely. Having some sort of audible alarm or notifications sent to your phone can help you to take action should something go wrong.
Have a backup heater on hand at all times or use two heating elements in your aquarium. Should the primary element break, you have a backup ready to go.
Run dual temperature controllers with something like your Neptune Systems Apex will provide redundant protection against heater failure and overheating.