The 5 Best Aquarium Heaters
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Keeping an aquarium is an exciting challenge completely different from keeping any other kind of pet. You fish will live in a captive underwater environment for their entire lives, so it is up to you to ensure that the conditions in your tank meet their needs. One of the most important aspects of caring for aquarium fish is maintaining a staple tank temperature and, for that, you need an aquarium heater.
In this article, we’ll talk about heating your aquarium and provide some tips for choosing the best aquarium heaters. You’ll also see our top 5 picks for the best aquarium heaters.
At a Glance: Best Aquarium Heaters To Buy
We highly recommend looking at the comparison table we have below where we highlighted the features of each product. You’ll also find more detailed information about each product later in the article.
Compare Best Aquarium Heaters
1. Cobalt Aquatics Flat Neo-Therm Heater
2. hygger 100W Mini Submersible Digital Display Aquarium Heater for Small Fish Tank
3. Aqueon Glass Adjustable Aquarium Heater
4. Eheim Jager Thermostat Aquarium Heater
5. Tetra HT Submersible Aquarium Heater with Thermostat
25w to 200w (6 to 55 gallons)
100 to 300 watt (10 to 60 gallon)
50w to 300 w (5 to 90 gallons)
100 watts (26 to 40 gallons)
50w or 100w (2 to 30 gallons)
Flat-back design, fully submersible, shatterproof
Submersible, heat-resistant, adjustable
Submersible, shatter-resistant, compact
Auto-shutoff, shock-resistant, shatterproof
Fully submersible, built-in thermostat
What To Look For In Aquarium Heaters?
There are two primary types of aquarium heater – hanging heaters and submersible heaters. The main difference is that a hanging heater attaches to the back or side of your aquarium using a suction cup while a submersible heater is designed to be completely under the water. Either model is perfectly fine, it just depends where you want to place the heater for the greatest benefit to your fish.
Here are some important things to look for in a heater for an aquarium:
- Size and rating. Aquarium heaters come in a variety of different sizes and they are rated for tanks of different capacity – choose one appropriate for your tank size.
- Programmable. Some aquarium heaters are programmed to maintain a specific temperature while others are adjustable, so consider what you want before you start shopping.
- Safety features. There are two primary safety features to look for in an aquarium heater. One is an automatic shutoff that prevents the heater from running when it is out of the water. The other is a thick, shatterproof housing to protect your fish.
- Price. You don’t want to shop for aquarium equipment by price alone, but it can certainly be a factor in making your decision. You want to strike the right balance between quality and affordability.
Our Top Picks For The Best Aquarium Heaters
Now that you have a better idea what to look for in an aquarium heater, it’s time to start shopping! Keep reading to see our top 5 picks for the best aquarium heaters.
Cobalt Aquatics Flat Neo-Therm Heater
- Brand: Cobalt Aquatics
- Watts/Rating: 25w to 200w (6 to 55 gallons)
- Features: Flat-back design, fully submersible, shatterproof
- Available in six sizes ranging from 25w to 200w
- Flat-back design and fully submersible
- Temperature range 66°F to 96°F, 0.5°F accuracy
- Somewhat expensive compared to other models
- Suction cups may not hold very long
This heater comes in six different sizes ranging from 25 watts to 200 watts, able to accommodate tanks as small as 6 gallons and as large as 55 gallons. It features a flat-back design for easy installation in your tank and it is fully submersible with a shatterproof housing. You can adjust the temperature between 66°F and 96°F with a single touch and the heater will keep to within 0.5°F.
hygger 100W Mini Submersible Digital Display Aquarium Heater for Small Fish Tank
- Brand: Hygger
- Watts/Rating: 100 to 300 watt (10 to 60 gallon)
- Features: Submersible, heat-resistant, adjustable
- Available in three sizes 100w to 300w
- Fully submersible with 9 temperature settings
- Heat-proof milky quartz is shatterproof
- Vertical installation not recommended, should be horizontal
- LED indicator light may be too bright for some
Aqueon Glass Adjustable Aquarium Heater
- Brand: Aqueon
- Watts/Rating: 50w to 300 w (5 to 90 gallons)
- Features: Submersible, shatter-resistant, compact
- Compact design available in five sizes
- Shatter-resistant quartz glass construction
- Automatic safety shutoff feature
- May not be recommended for saltwater tanks
Eheim Jager Thermostat Aquarium Heater
- Brand: EHEIM
- Watts/Rating: 100 watts (26 to 40 gallons)
- Features: Auto-shutoff, shock-resistant, shatterproof
- Fully submersible with TruTemp recalibration
- Made of shock-resistant and shatterproof glass
- Compact design and affordable pricing
- May be too long to install horizontally with ease
- Calibration process can take a few days
Tetra HT Submersible Aquarium Heater with Thermostat
- Brand: Tetra
- Watts/Rating: 50w or 100w (2 to 30 gallons)
- Features: Fully submersible, built-in thermostat
- Affordably priced and fully automatic
- Available in two sizes 50w and 100w
- Can be installed vertically or horizontally
- Only available in two sizes (50 and 100 watts)
- Not adjustable, heats to a single temperature
Tips For Heating An Aquarium
In addition to choosing the right heater for your aquarium, you also need to be mindful of things that could impact the tank temperature. Avoid putting your tank in the path of direct sunlight, for example, or anywhere near a door, window, or vent where it could be affected by drafts or air conditioning. If you live in a very warm and stable climate, you may not even need a heater!
Here are some simple tips for heating your aquarium:
- Choose an aquarium heater that is rated for your size tank or larger – there is no harm in choosing a bigger heater than you need, but you definitely shouldn’t go smaller.
- Read the directions for installation on the heater to double-check whether it can be fully submersed or if it needs to be kept partially above the water.
- Research the type of fish you are keeping in your tank to determine the ideal temperature range for that species and set your aquarium heater accordingly.
- Check your aquarium heater on a daily basis to make sure it is working – you should also install a thermometer to double-check the temperature.
Now that you understand what an aquarium heater can do and how various models are different, you’re ready to start shopping for the best heater for your particular aquarium. Consider what you’ve learned here and put that knowledge to use when making your decision.
Once you’ve chosen your aquarium heater, the next step is to install it in your tank and use it. If you’ve chosen a submersible heater, you should consider placing it a few inches below the waterline or at the bottom of your tank for more even distribution of heat. If you chose a hanging heater, place it in the middle of the tank so it disperses heat throughout.
If you’re still not sure where to start in looking for an aquarium heater, try out one of the top 5 best aquarium heaters we’ve reviewed above. Good luck!