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DaToo

Mini Aquarium Heater 25W Small Fish Tank Heater 25 Watt with Free Thermometer Sticker

  • Based on 4,750 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives Friday, Sep 5
Order within 14 hours and 18 minutes
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Size: 25W


Features

  • 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 78F. This temperature is very suitable for betta and most tropical fish. When the water temperature is lower than 78F, the heater starts to heat and the red light is on. When the temperature reaches 78F, 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!!
  • Safe And Durable: Unlike traditional plastic seals, DaToo uses a rubber sealing layer, which ensures that DaToo has better sealing and safety performance, and will never leak electricity or water. Quartz glass material, explosion-proof and crack-proof, more sturdy and durable, without worrying about damage.
  • One Year Warranty & Satisfaction Guarantee: This heater is ideal for 1 to 6 gallon small glass or acrylic desktop aquariums. When in use, it needs to be submerged 100% in water. We provide one year warranty and 24 hours professional customer service. Buy With Confidence!

Description

The Smallest 25Watt Aquarium Heater For Your needs Specification: Power: 25Watt Voltage: 110V~120V/50~60Hz Heater Size: 4.90.90.9inch Power cord: 3.9ft Application: 1 to 5 gallon aquarium Features: - The Smallest 50W Heater On The Market - 78℉ Constant Temperature - Rubber Sealing Layer - Quartz Glass Material - One Year Warranty And 24 Hours Professional Customer Service Why Choose DaToo MINI 25W Aquarium Heater? 1. No Need To Set: DaToo MINI 25W Aquarium Heater will automatically keep the water temperature constant at 78℉. Simple and convenient, very suitable for beginners. 2. The smallest 25W aquarium heater: Only 0.2 inches in length, the smallest 25W heater on the market. No matter how small your fish tank is, it can easily meet your needs. 3. Safe: Unlike traditional plastic seals, DaToo uses a rubber sealing layer for better sealing and safety performance, and will never leak electricity or water. 4. Durable: Quartz glass material, explosion-proof and crack-proof, more sturdy and durable, without worrying about damage. 5. One Year Warranty And 24 Hours Professional Customer Service, Buy With Confidence! Select DaToo Products= Own A Private Aquarium Housekeeper. JUST DO IT, Let’t Go!!

Brand: DaToo


Special Feature: Waterproof


Color: Black


Age Range (Description): Adult


Outer Material: Plastic


Display Type: Digital


Product Care Instructions: Wipe Clean


Unit Count: 1.0 Count


Power Source: Corded Electric


Item Length: 4.9 Inches


Package Dimensions ‏ : ‎ 5.43 x 2.8 x 2.28 inches; 5.11 ounces


Item model number ‏ : ‎ DT-25A


Date First Available ‏ : ‎ July 17, 2020


Manufacturer ‏ : ‎ DaToo


Best Sellers Rank: #2,704 in Pet Supplies (See Top 100 in Pet Supplies) #2 in Aquarium Heaters


#2 in Aquarium Heaters:


Customer Reviews: 4.3 4.3 out of 5 stars 4,750 ratings


Brand: DaToo


Special Feature: Waterproof


Color: Black


Age Range (Description): Adult


Outer Material: Plastic


Display Type: Digital


Product Care Instructions: Wipe Clean


Unit Count: 1.0 Count


Power Source: Corded Electric


Item Length: 4.9 Inches


Upper Temperature Rating: 78 Degrees Fahrenheit


Reusability: Reusable


Immersion Depth: 0.9 Inches


Lower Temperature Rating: 78 Degrees Fahrenheit


Indoor/Outdoor Usage: Indoor


UPC: 745408757995


Manufacturer: DaToo


Item Weight: 5.1 ounces


Item model number: DT-25A


Date First Available: July 17, 2020


Item Package Dimensions L x W x H: 5.43 x 2.8 x 2.28 inches


Brand Name: DaToo


Target Audience Keyword: fish


Size: 25W


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Sep 5

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • My fish are nice and cozy 💞
Size: 25W
Alright, fellow fish fanatics, gather 'round because I'm about to spill the tea on this Mini Aquarium Heater. I've got a 5.5-gallon tank that's basically the underwater equivalent of a studio apartment in NYC—cozy, but every inch counts. Finding a heater that doesn't turn my tank into a tropical hot tub has been a JOURNEY. But this little heater? Oh, honey, it's the Beyoncé of aquarium accessories. First off, let's talk consistency. This thing is like a Swiss watch, but for fish. I swear, it's got my tank water chilling at a solid 80°F. My fish are practically doing the tango, they're so happy with the stable temps. I even caught my snail giving it a little nod of approval. And the thermometer sticker? Okay, it's not exactly NASA-level tech, but it gets the job done. Plus, it's idiot-proof, which is crucial because, let's be honest, sometimes I feel like I'm just winging this whole fish-keeping thing. I stuck it on, and now I can glance over and make sure my aquatic pals aren't boiling or freezing. So, if you're tired of playing thermostat roulette with your fish tank, do yourself (and your fish) a favor and grab this heater. It's reliable, easy to use, and might just make you the coolest fish parent on the block. Trust me, your fish will thank you. They might even start paying rent. (Okay, maybe not, but a fish mon can dream, right?) ... show more
Reviewed in the United States on July 7, 2025 by Mika L
    • Great travel heater
Size: 25W
This was perfect for our travel tank. We took our beta fish with us on our camping trip and he didn't seem to mind the difference. The heater worked and held a steady 78 degrees the whole time. The price is perfect for a travel tank scenario. I would recommend this one to anyone with a smaller tank or traveling with their pets. ... show more
Reviewed in the United States on July 9, 2025 by Renee Martin
    • It's not just for fish you know.
Size: 25W
I bought this small heater for my Lotis plants. It is small, works great and easy to see the heat light. Just stick it on the tank wall and plug it in. The heater does the rest. Worth the buy for small tanks.
Reviewed in the United States on July 26, 2025 by Tracy
    • MINI AQUARIUM HEATER THAT WORKS
Size: 25W
I have a large glass bowl that I use as an aquarium for my small tropical fish and I got this heater to use in it because it is only 2-3 gallons in size and this heater is perfect for it. It works great! I have purchased small heaters before and had trouble with them i.e. not really able to control the temperature well, but this one seems to be working great and keeping the temperature right at the correct level for my tropical fish without overheating the small tank. So I am happy with it. It came with a free stick on thermometer which didn't actually work i.e. the temperature would not show on it so I pulled it off the side of the tank to throw it away and it left sticky residue on the outside of the tank which was difficult to remove. I think it was included so you could verify that it was keeping the temperature at the right level. So the small stick on temperature strip was a failure but using a regular thermometer in the tank shows that it is keeping the temperature at the correct level and the heater itself has a little indicator light which shows when the temperature is safe (green) and when it is too hot or cold (red) and that works. So I threw the temperature strip away because it did not work and with some difficulty I finally got it off the side of the tank. It left little sticky bits behind on the glass that I had to scrape off. But the little heater works great and has its own internal safety indicator light where red equals out of safe range and green means it is safe and that does work. But the external strip thermometer didn't work and when I tried to remove it from the outside of the tank it was difficult to get the sticky adhesive off the side of the tank as some of it pulled off the little strip and stuck to the exterior of the tank glass and was difficult to remove from the glass. So I threw the small thermometer strip away as it was useless i.e. no temperature showed on the strip after a full day but the heater itself is great. ... show more
Reviewed in the United States on October 10, 2024 by SMALL AQUARIUM OWNER
    • Works great and keeps the temperature very consistently at 80°>
Size: 25W
My wife has a couple of three to five gallon aquariums that she has show guppies and amano shrimp in one and an outstanding betta in another and keeping the temperature at the correct point consistently is very important. We've compared them with manual thermometers and they are very accurate. They are solidly built and very simple to slide down into the space where the pump and filter are and they stay in place nicely with the included suction cups. There's no fiddling with a manual thermostat - just plug and play, as they say. We've used these for years and definitely recommend them. ... show more
Reviewed in the United States on June 20, 2025 by Gahvno
    • Okay... Let's actually talk about aquarium heaters.
Size: 25W
I have been keeping freshwater aquariums on and off for almost 30 yrs. Heaters have always been the same tech they are now. The BIG takeaway is to keep them cool and constantly sampling flowing water. I have ALWAYS set mine up by the pump outflow and kept them completely submerged. DO NOT keep them plugged in while changing water. This lowers overheating and temperature component shock which leads to a lot of the issues seen in the reviews here. If you have a betta in a setup with no water flow... do not get a heater until you have an actual tank setup. STOP putting these in bowls and expecting them not to blow up. Temperature accuracy and what I have learned with this unit... I keep mine in the pseudo sump unit in the 5 gallon kit I bought. This way water is constantly flowing around the unit. I have an air stone in this same compartment and when it is running it cools the unit more which lead to it running between 80 F - 78 F. When the bubbler is off it cycles and stays a consistent 78 F. So, over agitation can lead to the unit sampling too cool and cycling more. So, I have put my bubbler on a timer and do spaced out 30 min cycles throughout the day. This has resolved the issue with this unit. It needs gentle water flow for accurate sampling and heating. Over agitation can lead to it falsely reading the water as cooler leading to the varied warmer temps. ... show more
Reviewed in the United States on April 27, 2025 by Jelleesi

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