10 Best 300w Aquarium Heater
Updated on: June 2023
Best 300w Aquarium Heater in 2023
Orlushy Submersible Aquarium Heater 300W-Fish Tahk Heater with Adjust Knob Thermostat 2 Suction Cups Suitable for Marine Reef Fish Tank Sump
Aqueon 100528589 Glass Submersible Adjustable Heaters,Black,300 W

- Precise temperature setting to 1-degree F (68-88 degrees F)
- Recommended for aquariums up to 40-Gallons
- Shatter-resistant construction, fully submersible
- LED light turns on when aquarium water is being heated; Automatic safety shut off and overheat protection
- Lifetime Limited Warranty
EHEIM Jager Aquarium Thermostat Heater 300W

- Fully submersible
- Thermo safey control protects against running dry
- Will automatically turn off when water level dips too low
- TruTemp dial recalibrates the heater for precise temperature regulation
- Made of shock resistant and shatter proof glass for fresh or marine water
- On/Off indicator light for at-a-glance monitoring
300w 150w 50w Submersible Aquarium Heater Auto Thermostat Heater with Suction,LED Small Mini Temperature Display Aquarium Fish Tank Heater for Fish Tank Water (Bonus Thermometer)

- UPGRADED MORE DURABLE VERSION: Provided the best warm area to your fish in the cold winter.Keeps improving best aquarium heater for your fish tank, after collecting so many comments from customers, we upgrade its function and life time, now it works more continuously and accurately.
- MORE SAFETY & HIGH QUALITY: This upgraded aquarium heater now updated for more durable Quartz Glass, which is pretty shatter-proof and blast-proof and prevents electricity leakage. And the stronger protective container updated for Anti-melting anti punching double sealed material, it is scald-preventing for your pets and your safety.
- FREE THERMOMETER: This fish tank heater come with an extra thermometer to show the accurate tank temperature to avoid overheat or freeze. It provide a constant warm environment for your pet fish to stay healthy, suitable both for fresh and salt water.
- TEMPERATURE CONTROL: Aquarium heater works in intermittent operation mode and will automatically turn on/off to achieve the setting temperature constantly and stably. Setting the temperature by the red knob on the top with range is 64°F - 94°F.High accuracy(±1°F)
- APPLICABLE TANK SIZE: Our submersible aquarium heaters are perfect designed for different size tank, 50W for 5-10 gallon; 100W for 10-30 gallon; 300W for 30-85 gallon, please choose the suitable power for your tank. And we also recommend to position it near a strong water flow, the outlet of a power filter is ideal, so that the whole aquarium are in the same temperature.
VIVOSUN 300W Aquarium Heater Submersible Titanium Fish Tank Heaters with Intelligent LED Temperature Display and External Temperature Controller

- PRECISE TEMPERATURE CONTROL: An intelligent IC chip controls the heater temperature, making the temperature difference within ±1℃/±2ºF; Provide the best living environment for your aquatic creatures
- SAFETY GUARANTEE: Made with IP68, the highest waterproof level; and a titanium tube material that features explosion-proof and anti-corrosion engineering, which makes this submersible heater more resistant to damage while heating better than traditional glass heaters; Built with overheat and water shortage protection
- EXTERNAL TEMPERATURE CONTROLLER: The touch-button controller adjusts the temperature without getting your hands wet. It’s easy to control the temp from 68℉/20°C to 94℉/34°C; Check the size chart to find your desired fish tank heater
- EASY TO SETUP: 300W submersible heater is suitable for 50 to 60 gallons aquariums; Vertical or horizontal installation and ensure the device is fully submerged underwater
- WIDE COMPATIBILITY: The fish tank aquarium heater has CE, FCC and ROHS certification and the plug has a UL certification; Applicable for freshwater and marine aquariums, aquaculture, glass containers, and hydroponic systems
ViaAqua 300-Watt Quartz Glass Submersible Heater with Built-In Thermostat

- High quality quartz glass
- Fully-submerisble
- Visible temperature setting
- For use in fresh or saltwater aquariums
Hygger 500W Digital Quartz Aquarium Heater for Fresh-Water and Salt-Water, with External IC Thermostat Controller and Thermometer, Fast Heating Submersible Thermostat for Fish Tank 60-120 Gallon

- 🐠【Fast Heating Up】voltage 110-120V/60HZ, power 500W, US three-pin plug, heater rod length 10.5 inch, 500W submersible heater for fish tank 60-120 Gallon. The heater power cord is 6ft, the controller power cord is 5ft, the thermometer cord is 4.6ft. Temp range: 61-90℉. Fast heating up aquarium heater, it takes about 3 minutes to heat 3.5 gallon water up 3℉
- 🐠【Fully Automatic Control】very easy and reliable to use. After finishing the temperature setting, the fish tank heater will run automatically by itself. It will stop heating when the water temp reaches to the set temp, please note that the water temp may go up 1℉ more because of the waste heat. When the water temp is cool down to 1℉ less than the set temp, the tank heater will restart heating
- 🐠【Quartz Tube & Plastic Guard】With high-quality quartz glass tube, it's very durable and explosion-proof, this fish tank heater can be used for saltwater and freshwater aquariums, service life can be 3 years or more. With low profile black plastic guard, easy to hide in the tank. The guard can prevent your aquarium pets from burned, the gaps on the guard is about 3mm, no worries for fish stuck
- 🐠【Digital LED Display Controller】the external IC temp controller can show the water temp with 2 blue LED digits. Only show Fahrenheit degrees. To set the temp, just press the button over and over until the screen displaying the temp you desired, then stop and wait the digit flashing for 3 times, the setting is done and the led shows the current water temp again. The controller is connect with separate sensitive thermometer
- 🐠【Fully submersible Aquarium Heater】with strong suction cups on the heater guard and the thermometer, it's easy to install the aquarium heater no to the tank walls or bottom, please keep them fully submerged. The thermometer should be away from the heater and keep water circulation as far as possible
Marineland ML90654 Precision Heater for Saltwater or Freshwater Aquariums, 300-watt

- This 300 watt heater is for aquariums up to 80 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
- Advanced mounting bracket securely attaches to glass and provides 3 window positions to view the temperature display
- Easy to view sliding scale tells the exact temperature setting. Top dial view shows the setting from an additional location.
Hygger 500W Aquarium Heater with LED Digital Temperature Controller, Submersible Fish Tank Water Heater for 60-120 Gallon Tank

- This fully submersible aquarium heater enables memory function and over heat protection. Auto shut off when over-heats, resets when it cools down.
- Made with premium quartz and double sealed by black protective guard, this fish tank heater is resistant to explosion and corrosion, and protect fish and other livestocks from punching and scalding
- Build-in external IC temp controller, easy to read blue LED digital number shows real time water temperature. Heat indicator lights on red when fish heater start to heat and turns in yellow once it reach set temperature. Temp accuracy is +/- 1°F.
- Easy to set temperature without getting hands wet. Temperature can be precisely adjusted from 61 to 90°F (16°C ~ 32°C). Just press set button to desired temperature, it blinks 3 seconds and begins to work
- 500 watt aquarium heater, voltage 110-120V, suitable for tank capactiy 60-120 gallon freshwater and saltwater aquariums
Zacro 300W Submersible Aquarium Heater, Auto Thermostat Fish Tank Heater with Protective Sleeve and Digital Temperature Readout

- Our aquarium heater is suitable for the fish tank which is up to 80 Gallons, Voltage/freq: 110-120volt/60hertz; Power: 300W.
- Waterproof: Adopt double sealed materials - plastic and black protective container, which is helpful for Scald-preventing and anti punching.
- Collocation: Comes with an thermometer to show the accurate tank temperature to avoid overheat or freeze.
- Function: Our aquarium heater can provided a warm area to your fish in the cold winter.
- Attention: DO NOT power until the heater is completely submerged in the water.
Setting Up a Freshwater Aquarium: What First-Timers Need to Know
This article briefly discusses the basics of setting up a freshwater aquarium for the first time.
Setting up a freshwater aquarium for the first time is a lengthy, albeit rewarding experience. I have set up a few freshwater aquariums of my own over the years and can offer up a few suggestions on how to get the job done. Here they are:
Cleaning the Tank
Start by thoroughly washing your hands and the fish tank to avoid the introduction of any unwanted materials into your new pet's home. When washing your fish tank, I'd recommend that you avoid using detergent or other commercial cleaners that could leave an unseen residue behind. I have always had success washing my new fish tanks with rock salt. I find that it cleans the tank safely and efficiently.
For the first cleaning, I'd suggest creating a mixture of water and rock salt. Then dip a sponge or lint free cloth in the mixture and use it to wipe down the inside of the tank. You can also use the rock salt as a gentle abrasive if you need to remove a price sticker from the tank. Once you are done wiping the inside of the tank down with the salt water, make sure that you rinse and dry it thoroughly as well.
Installing the Background
Some of you may have purchased a background decal or crystal paint to coat the back of the tank in the hopes that it will make the tank more visually pleasing. Personally, I tend to avoid such things. I like the natural look better. If you did purchase such an item, now is the time to apply it.
Setting Up the Fish Stand
Once that's done, it's time to set-up the fish stand. Make sure that you are happy with the location before you go ahead and add the water to the tank. Otherwise it will be a big hassle to move it. You'll also want to make sure that everything is level by using a carpenter's level. I have never had much luck leveling fish tank stands without one.
Adding the Gravel
Before you add the water, you'll need to complete a few more tasks. Open the bags of gravel that you purchased for your tank and rinse off any residue. I have found that using a kitchen colander is helpful in such applications. If you decided to go with an under-gravel filter, go ahead and install it into the fish tank now.
After the gravel has been rinsed off, place it at the bottom of the fish tank. If you are using an under-gravel filter, make sure that you read the manufacturer's instructions carefully and situate the gravel as directed. Those that are not using such a filter should allow a gravel depth of two to three inches. In my experience, the gravel should also be graded so that it has a slight slope. The top of the slope should be at the rear of the tank.
Adding the Ornamentals
Keeping your fish tank's size and lighting capacity in mind, proceed by adding your ornamental items. I have found that when it comes to fish tank ornaments, less is more. Once everything is in place, carefully add the water a little at a time so as not to disturb your set-up. I'd recommend only filling the tank up half way because you still have more work to complete. You'll also need to let any sediment that rises during the filling process to settle. If there is too much sediment, you may need to empty the tank and start again.
Installing the Heater, Filter, Aerator and Plants
Continue by installing your fish tank's heater, filter and aerator according to the manufacturer's instructions. Then turn your attention to any plants you may have purchased for your fish tank. Go ahead and plant them into the gravel using a pair of planting tongs. Try to keep your hands out of the water so you do not accidently introduce foreign materials into the fish tank. Afterward, finish filling the tank with water.
Preparing the Water and Adding the Fish
Next, get the heater and filter running. You'll also want to add chlorine neutralizer and some coarse salt to the water. I typically add two teaspoons of salt to a 10-gallon tank. I'd also recommend checking the water's pH level with a test kit to make sure that it is appropriate for the fish you purchased. Allow the fish tank to sit unoccupied for 48 hours to give everything a chance to settle down.
After the 48 hours have past, you can usually start to add the fish to the tank. I would recommend that you discuss with your local pet shop owner how to add the fish to the tank. In most instances the water will need to be at a certain temperature before the fish can be added safely. Different species of fish require certain water temperatures and pH levels, that's why it best to talk it over with the store owner. He or she can generally provide proper guidance in such matters.
Over the course of her lifetime, Killeen Gonzalez has maintained both fresh and saltwater, home aquarium set-ups.