Best 5 Gallon Fish Tank Heaters in 2026

【25W Aquarium Heater】Orlushy 25w fish tank heater can be applicable to 1-6 gallons tank. It is 4.7 inches in length, ideal for use in low water level and won’t take up mech place, easy to hide in small tank. Please fully submerged the heater vertically into water in fish tank, and horizontally into water in turtle tanks.

【Easy to Operate 】This aquarium heater is automatic constant temperature heating when the power is switched on. The preset temperature is 78℉. Accuracy is ±3℉. Stair shape heating that red light is on and heater starts to intermittently heat the water to the preset temp, saving energy and electricity. When green light is on, heater stops working and maintains constantly 78℉.

【Durable & Material】 The durable material of the heater ensures safe operation. The outer shell covering the whole body of the heater is made of heat-resistant ABS material that it won’t deform and melt under high temperature. The heating rod is made of nickel-chromium heating wire to faster heating rate, and non-corrosive quartz glass.

All Tetra HT heaters have indicator lights to let you know when the heater is on. It will be red when heating and green when the proper temperature has been reached.

The HT10 uses a built in electronic theromstat to automatically maintain water at 78° F which is ideal for most tropical fish. No adjustment is requried.

Ideal for aquariums between 2 to 10 gallons with hoods or glass canopies

Aquarium heater that blends into the aquarium environment with built-in reflective technology that mirrors the surrounding colors

Computer-calibrated thermostat and easy-to-adjust temperature control dial

Shock resistant Borosilicate glass and high density ceramic heat sick

Explosion Proof: The aquarium heater is made of 2mm thickened quartz glass, 33% thicker than ordinary glass, explosion-proof, not easy to crack, which is very safe for people and aquatic animals.

Application: 100W water heater is suitable for 10–30 gallon tank, also suitable for both saltwater and freshwater, suitable for fish tanks and turtle tanks, must be completely submerged in water when using.

Accurate Temperature: The fish tank heater can be adjusted from 68°F to 93°F (20°C - 34°C), comes with a thermometer sticker, convenient to detect the water temperature without another pay.

For 5-20 Gal Tanks: Measure 8.5 inches in length. Applicable for aquaculture and fresh, marine and tropical aquariums. Save your fish or plants from coldness to keep them vigorous.

Adjustable: Controllable temperature range from 68 °F to 93 °F (20-34 °C). Simply rotate the knob to freely regulate the temperature with deviations from ± 2 °F to ± 4 °F.

Detect Temp Timely: With a built-in thermostat, it will automatically keep the water at the set temperature. The extra thermometer sticker allows you to detect water temp at any time.

Superior Safety and Enriched Ambiance: The fish tank heater is constructed with high-quality shatterproof glass and BPA-free plastic, ensuring a safe habitat for your fish. Aquarium heater 50W, power cord 4.75ft, designed for most fish tanks, recommended for aquariums up to 100 Gallons.

Precision in Temperature Control: This aquarium heater excels in providing a customizable temperature range of 68°F-93°F, catering to various aquatic species. Suitable for freshwater and saltwater tanks, it creates a natural environment for your finned friends.

Compact, Versatile, and Efficient: Whether you have a small aquarium heater 5-gallon tank or an aquarium heater 55-gallon setup, this compact heater can be placed horizontally or vertically. Position near a filter or pump for even heat distribution.

★【Betta Heater】This Fish Tank Heater should be 100% submerged into water, Ideal for small glass or acrylic desktop aquariums up 1 to 6 Gallons, not suitable for less than 1 gallon tank.

★【Quick and Easy Installation】:Vertical or horizontal placement using, Aquarium heater automatic temperature control 78℉, no need to adjust temperature, easy to operate, fishes happy.

★【How it Works】: Plug in, red light turns on, the heater will start working until water temperature up to 78°F, and red light off, then the green light will turn on, heater stop working and keeping constant temperature 78°F. Accuracy：±3°F

🐟HITOP aquarium heater 50W, length 7.2-inch, power cord 4.9ft, designed for small fish tanks, recommended for aquariums up to 15 Gallons.

🐟 Thickened Glass: 2mm thickened quartz glass, 33% thicker than 1.5mm normal aquarium heaters, much safer for human and your lovely fishes, your pets will no longer fear the winter.

🐟Adjustable and easy to use: This aquarium heater, adjustable temperature range 68 ~ 93 °F, after setting the temp you want, will on or shut off automatically when the water temperature changes, no extra adjustment is required.

Preset to 78 degree, accurate to plus/- 1 degree

No adjustment required

Shatter resistant

🔥【Explosion-proof Quartz Glass Aquarium Heater Durable and Safer】The heater made of explosion-proof quartz glass material and a high-temperature resistant nickel-chromium heating wire with silicon carbide heat conduction,faster water heating and long lasting.2 hours heating 1℃.The shell is a high temperature resistant PC material, which can effectively protect the fish from scalding.

🔥【Temperatures Ranges 68℉ to 93℉,Automatic Heating】The heating rod built-in thermometer,When the water temperature is lower than the set temperature by 1℉, the heater will automatically heat up, and stop heating when the water temperature is consistent with the set temperature.Fahrenheit and Celsius can be converted to each other,Pressing and Press and hold "+" and "-" at the same time, Fahrenheit and Celsius will be converted into each other after 5 seconds.

🔥【LED External Controller with Indicator Light】The controller is not waterproof, please keep away from water，LED digital display screen shows the current water temperature and preset temperature.The number the left on the controller is the current water temperature, and the number on the right is the set temperature,torch light and surrounding lights flicker means heating,torch light and surrounding lights not flicker indicate constant temperature.

【Aquarium Heater 200W】-- The 200W aquarium heater produces stable power with quick heat up. It's length is 8.3'', voltage 110-120V, power cord is 5.9ft (cable wire: 4.6ft, power wire: 1.3ft) . Aquarium heater for 20 to 40 gallons, ideal uses for the marine saltwater and freshwater, fish tanks, turtle tanks, betta tanks, small ponds, and so much more.

【Safe and Durable Fish Tank Heater】--The components of this 200W fish tank heater are designed for safety and durability, and encased in a high-durability ABS shell. The nickel-chromium heating wire and quartz glass are made of high-temperature resistant materials, along with explosion-proof quartz sand, giving the product a high level of safety and durability.

【Comprehensive Protection Submersible Aquarium Heater】 -- Our submersible aquarium heater have 2 intelligent protector to avoid damage to the product and its circuitry. ①Over max temp warning, when the temperature is higher than the maximum temperature 94℉/34℃, the code HH appears and automatically stop heating. ②Off-water warning, when the submersible aquarium heater is higher than the level of the fish tank water code E1 appears and automatically stop heating.

🐠25W Betta Aquarium Heater: Creating and maintaining a perfect and comfortable water temperature for our cute fish is not easy, which requires a lot of effort. Now DaToo MINI 25W Aquarium Heater can help you make this easier. Precise and constant temperature, no need to set, keep the temperature of fish habitat in the best state at all times. You will find it very easy and happy to take care of pet fish！

🐠Precise And Constant Temperature: No need to set, DaToo Fish Tank Heater will automatically keep the water temperature of the fish habitat at 78℉. This temperature is very suitable for betta and most tropical fish. When the water temperature is lower than 78℉, the heater starts to heat and the red light is on. When the temperature reaches 78℉, the heater stops heating and the green light is on. DaToo will always maintain this comfortable temperature for your beloved fish!

🐠The Smallest 25W Betta Heater: For most fish lovers who have small fish tanks of 1 to 5 gallons, a small heater means more space for fish. This is the smallest 25W aquarium heater on the market, only 0.2 inches. No matter how small your fish tank is, it can be used perfectly in it, and you can't even find it. Very MINI!!

This 50 watt heater is for aquariums up to 12 gallons. Adjustable temperature dial allows you to set the temperature 1 degree with every click.

Thermal Switch automatically turns off as temperature rises above an internal preset and turns back on once it cools down.

The advanced heating element contains a mica core surrounded by a mesh heating element for superior heat transfer with enhanced durability

FREESEA Aquarium Heater: 75w betta fish heater, voltage: 110~120V, is suitable for use in 5-15 gal betta fish turtle tanks and aquariums. The power cord is 5ft, long enough for indoor use

Double Safety Protection: When the top part of the turtle tank heater is out of water it will auto shut off. When the actual water temperature is higher than 94°F, it will auto activate the overheating protection and stop heating

External Controller: The betta fish heater is adjusted by an external controller, which you can mount on the outside edge of the tank. It’s convenient to adjust temperature that range from 63℉ to 94℉

【50Watt Heater】This Aquarium heater is suitable for 8 to 16 gallons aquariums, voltage 110-120V/60Hz, power cord is 5.0 ft, please choose the right wattage aquarium heater according to our size chart.

【Temperature range】: 68°F to 93°F (20°C - 34°C) , It is very easy to adjust the temperature you need (Temperature accuracy: ±3℉). we also deliberately give each customer a Thermometer Sticker you can observe the water temperature of the fish tank at any time.

【Safety & Blast Resistant】2mm thickened quartz glass, 33% thicker than the normal, safer for both human and pet, heater can be used in fresh water and salt water aquariums,easy to hide in the tank.

FULLY SUBMERSIBLE AQUARIUM HEATER: The 25W Cascade Aquarium Heater easily maintains healthy water temperature within a 1° accuracy, and can be set anywhere between 68 ℉ and 89 ℉, by using the red control knob. The 25W model works great for fish tanks up to 5 gallons.

VISIBLE & ACCURATE TEMPERATURE SCALE: With an easy to read setting scale in both Celsius and Fahrenheit, it’s easy to see the temperature adjustments being made. To increase the temperature, rotate the control knob counter-clockwise, and to decrease, rotate it clockwise; or, follow the + and – symbols located near the control knob.

ORANGE PILOT LIGHT: Our Cascade Heat Aquarium Heaters feature a pilot light that indicates the heating cycle status. This means that it will go on and off by itself as the thermostat cycles the heating element on and off. In other words, orange light = heater is on. Similarly, these aquarium heaters make a faint click when turning off.

Preset temperature has been set to 77°F, appropriate for most tropical fish, shrimp and aquatic plants requiring stable conditions

With accuracy of ±2°F and overheat protection, protect your tank from extreme temperature

LED indicator light will turn to red when the heater is actively heating

【External Digital Display Controller】With its easy-to-use LED digital screen simultaneously displays the set temperature and the current aquarium temperature. You’ll be able to set temperature up in a healthy range of 59 to 93°F with button and monitor how well the heater is doing its job in real-time.

【Double Tubes Heating Element】Featuring shatterproof quartz glass tube + nickel-chromium heating wire for fast, steady, more evenly distributing heat. With a PC plastic guard to protects your fish touch it they won’t get burnt.

【Running-Dry Shut Off Protection】This is a completely submersible heater that will stop working when exposed to air and display error code "E1", which resets itself to resume working when placed back into the water.

🐟RAPID HEATING: Faster warming by seconds, the heater material is explosion-proof quartz glass, and nickel-chromium heating wire materials has higher thermal energy efficiency, and then conducts heat through silicon carbide material, is safer and more durable to use. High temperature resistant plastic cover, not easy to deform, and has very strong corrosion resistance.

🐟FREQUENCY ENERGY-SAVING: Auto reduces power when approaching the set tempe, by heated at 10% to 30% power, fully utilizes thermal energy inertia to smoothly reach the set tempe, saving energy. The external controller is easy to operation, every press changes the set tempe by 1℉, ranges from 59℉(15℃) to a max of 93℉(34℃) in order to meet your needs.

🐟INTELLIGENT THERMOSTAT: Over-temperature protection prevents "cooking fish". When the water temp exceeds about 95 °F, flashing 95 number code, red and green light flash together; and over 93℉, the heater will stop heating automatically. When the water temp cool down to below 93℉, the heater will start working auto.

Fully submersible

Vertical or horizontal placement using suction cups that mount to the bottom or side wall of tank

Quick and easy installation

🐟HITOP Mini size aquarium heater 50W with controller, suitable for seawater and freshwater heating, betta fish and turtle tanks and other small fish tanks or fish bowl 5-15 gallon.

🐟Easy to operate: This fish tank heater is easy to use, 6Ft long cable wire and the external controller can easily set the temperature, and the temperature adjustment range is 68-93℉.

🐟Easy to read temperature: The controller of this heater has Digital LED temperature display, which can display the real-time water temp and set temp, so that you can know the temperature changes in the fish tank easily. There is also a clear heating indicator on it.

The Slim heater will increase the water temperature of mini aquariums up to 10 gallons by a few degrees compared to the ambient room temperature. The Slim heater can be used in glass, acrylic, plastic fish bowls and aquariums. Safe to use under gravel. Please note, Slim heaters are not suitable to be used in environments without water

Extra small slim fish tank heater 150 is a great choice for Betta fish and for fish tanks 5 to 10 gallons, measures 6.1L x 3.2 inches, 15 watt; Plug and Play universal fish tank heater; No temperature to set; slim heater provides warmth for betta fish without taking up much room

Heater can easily be placed submerged in water or even under the tank gravel; The 90 degree angle makes this great for Betta acquariums; Safe to use in glass, plastic and acrylic fish tanks

PERFECT MINI HEATER FOR 1~1.5 GALLON TANK - For a Betta breeder with a 1 to 1.5 gallon small tank, it is very difficult to choose a suitable heater. Because most of the heaters on the market are too big for this small tank. This not only affects us to watch our beautiful Betta, but also reduces the activity space of the Betta. Now DaToo Mini Aquarium heater can help you solve this problem. Ultra-small and thin size, perfectly hidden in a 1~1.5 gallon tank, your Betta will be happy with it! !

CONSTANT TEMPERATURE & NO NEED TO ADJUST - DaToo 10W MINI Aquarium Heater can automatically maintain a constant temperature between 75°F and 82°F (depending on the external environment), no need to set. This temperature range is ideal for most tropical fish and is very beneficial for the reproduction of betta and promotes their metabolism. With no extra work, just plug it in and the DaToo 10Watt Small Fish Tank Heater will help your fish stay healthy and comfortable. Great for kids!!

24V SAFE VOLTAGE & POWER OFF AFTER LEAVING WATER - The output voltage of the DaToo Betta Heater is only 24V, which not only ensures the safety of the fish, but also ensures the safety of the user. No need to worry about leakage, you can rest assured to use it for your children. The Betta heater needs to be completely submerged in the water. If it leaves the water, it will automatically stop heating to prevent dry burning (heating indicator is green), which is very safe.

SUPER MINI SIZE – This small aquarium heater is “thumb size” - only 2.36” (6cm) in length. Great for nano tanks / betta tanks. The innovative super mini size perfectly solves the headache of the fish keepers on the traditional heaters! Takes up less space, easy to hide, but in full power! Temperature range is 64-93F, for 4-6 Gallon tanks.

ACCURATE TEMPERATURE – Thanks to the intelligent inverter technology, with the in-built chips this thermostat keeps the heater at a constant temperature at an accuracy of 1F, much more accurate than the traditional knob-controlled heaters. The thermostat shows 2 readings – the current temperature and the set temperature – very easy to operate.

DRY RUN / OVERHEATING PROTECTION – Full consideration of safety. With the multiple protections this fish tank heater will stop working when the water level is lower than the minimum water level or when the water temperature exceeds 97F. You are free from “cooking fish”!

Tetras Thrive When Right Temperature Is Provided --- Neon tetras, in their native Amazon habitat, live in a temperature range between 70°F to 81°F. This ensures their optimal comfort and metabolic efficiency. Any temperature below 70°F will cause your tetras to enter a state of minimal activity and they will be stressed and miserable. Make sure they are at their optimal health and performance with this heater.

Automatically Reaches The Preset Temperature --- The smart SunGrow heater for freshwater fish has a built-in electronic thermostat to automatically maintain water around 75°F which is ideal for most tropical fish. It saves you from the trouble of constantly keeping a check on the temperature of your tank. It will automatically shut down when it reaches the desired temperature, no manual adjustment is needed.

Fully Submersible Water Heater --- This 10-watt aquarium heater supports 1.5 gallons (5 liters) fish tank. Its exterior is designed tougher than glass and the sealed polymer can be submerged into your tank. The heating element is surrounded by thick plastic to ensure the protection of your fish.

AQUARIUM HEATER: Submersible heater is designed to keep your aquarium at the optimum temperature.

AUTOMATIC THERMOSTAT: Electronic thermostat keeps water at a consistent 78 degrees.

INDICATOR LIGHT: The red light shows when water is heating; green indicates that the heater is on standby.

Hydor Theo 50-Watt Aquarium Heater is a fully submersible; shatter-proof glass aquarium heater ideal for 5-to-14-gallon fish tanks; measures 7 inches long

Maximum Safety Aquarium Heater; THEO fish tank heater is shock resistant thanks to the patented PTC heating element and the shatterproof glass tube

Free positioning in aquarium with supplied suction cups; The Theo aquarium heater can be placed in the fish tank vertically, horizontally and fully submerged

✅Upgraded Heater - Our aquarium heater is made of high quality real quartz glass material, will not explode during working, can totally keep your fish safe and health, suit for freshwater and saltwater tank.

✅Circulating Working Mode - Our submersible aquarium heater has a super good feature is after setting your temperature, it will work about 5-10 minutes, then stop 2 minutes, then continue to working, repeat this working mode until get your temperature. This working mode avoid overheating your fish.

✅Adjustable Temperature – The temperature of the water heater can be adjusted, rotate the orange dial can easily set the accurate temperature which you want. Temperature range is 20-34 ℃(68-93 ℉).

SMALL AND POWERFUL: This mini aquarium heater is about 2 "long, and is super small. It is specially designed for small fish tanks and does not occupy any space. Upgrade the chip to make the temperature sensing more sensitive and the temperature rise more accurate.

INTELLIGENT MEMORY FUNCTION: After setting the target temperature, the power is suddenly turned off, and the target temperature remains unchanged after turning on the power again.

OVERHEATING PROTECTION: Built-in temperature sensor, temperature range 64-93°F. If the water temperature exceeds 95°F, the error code "HI" appears, the heater stops working, and when it returns to below 95°F, the error code disappears and it starts working again.

🐠【50W Compact Fish Heater】110-120V/60HZ square shape design small aquarium heater, fast heating for small fish tank. 50W tank heater is for 3-10gallon, 100W tank heater is for 10-20 gallon. The power cord is 5ft, long enough for use indoors. With 2 strong suction cups at the back side of the betta heater, it's easy to install it on to glass, acrylic or plastic tank

🐠【Shut off When Out of Water】BOEESPAT aquarium heater adopt newest technology, it is a fully submersible aquarium heater for fresh water and saltwater tank, when the top part of betta fish heater is out of water it will be forcibly stopped. After putting it in the water again, the fault disappears and normal operation resumes.It is a safe and reliable water heater tank

🐠【Small Aquarium Heater with External Controller】You can set the temperature outside the fish tank through the external controller, and the fish tank accessories of temperature sensing built in will cyclic heating the tank water automatically .Temp range from 65℉ to 93℉. Every time you set your betta fish heater, just press the button over and over until it reaches to your desired temp, then stop and wait the digit flashing for 3 times, then setting is done