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PULACO 25W Small Aquarium Submersible Betta Heater with Free Thermometer Strip, Under 6 Gallon Fish Tanks (Preset Temperature 78℉)

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Availability: In Stock.
Fulfilled by Amazon

Arrives Tuesday, Oct 7
Order within 20 hours and 51 minutes
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Model: 25 Watt-Under 6 gallon


Features

  • 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 78F, 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 78F, and red light off, then the green light will turn on, heater stop working and keeping constant temperature 78F. Accuracy:3F
  • Note: Do not operate or leave product plugged in when your water tank is out of water, heater should be fully submerged into water. Please install a water pump or filter to help water circulating while heating.
  • SATISFACTION GUARANTEED: Our Aquarium Heater is built with durability in mind and safety for every design. In the remote possibility that youre not satisfied with our product, just contact us, and we will gladly give you a new Aquarium Heater replacement. 12 Month Warranty and 24 Hour Professional After-sales Service.

Brand: PULACO


Special Feature: High Accuracy


Color: Transparent


Age Range (Description): Adult


Included Components: heater


Outer Material: Glass


Specification Met: CE


Display Type: Analog


Product Care Instructions: Wipe Clean


Unit Count: 1.0 Count


Product Dimensions ‏ : ‎ 5.5 x 1.2 x 2.7 inches; 4.2 ounces


Item model number ‏ : ‎ 25W


Date First Available ‏ : ‎ November 18, 2019


Manufacturer ‏ : ‎ PULACO


Country of Origin ‏ : ‎ China


Best Sellers Rank: #3,850 in Pet Supplies (See Top 100 in Pet Supplies) #4 in Aquarium Heaters


#4 in Aquarium Heaters:


Customer Reviews: 4.3 4.3 out of 5 stars 11,259 ratings


Brand: PULACO


Special Feature: High Accuracy


Color: Transparent


Age Range (Description): Adult


Included Components: heater


Outer Material: Glass


Specification Met: CE


Display Type: Analog


Product Care Instructions: Wipe Clean


Unit Count: 1.0 Count


Model Name: PL-Heater


Item Length: 4.9 Inches


Upper Temperature Rating: 93 Degrees Fahrenheit


Response Time: 500 Milliseconds


Reusability: Reusable


Immersion Depth: 12 Inches


Indoor/Outdoor Usage: Indoor


UPC: 763032017889


Manufacturer: PULACO


Item Weight: 4.2 ounces


Country of Origin: China


Item model number: 25W


Date First Available: November 18, 2019


Item Package Dimensions L x W x H: 5.51 x 3.62 x 1.81 inches


Item Dimensions LxWxH: 5.5 x 1.2 x 2.7 inches


Brand Name: PULACO


Target Audience Keyword: fish


Directions: Adults 18 years and older


Warranty Description: 1 YEAR


Specific Uses for Product: fish tank heater


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Oct 7

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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Top Amazon Reviews


  • SATISFACTION GUARANTEED!
Model: 25W
First of all, I buy a LOT of STUFF on Amazon and I almost never give reviews. Why? Because I'd be spending an un-Godly amount of time just writing reviews so I skip it. However, I HAVE written reviews. What motivates me to write a review when usually I just SKIP IT? What motivates me is when I receive a product from a buyer on Amazon that blows my socks off and is BEYOND my expectations. I have bought many thermometers over my fish keeping years. Left the hobby for awhile (I should say, "Left the Lifestyle') & when I came back LO & BEHOLD, Nano Tanks are the rage. Nano tanks and I am very fond of planted glass bowls (I'm about to try a new Walstad bowl- CYS-EXCEL 13.5"h x 15.25" across on Amazon) Consequently, I have purchased many, many small heaters for my smaller glass bowl and a 7.11 gallon 11.8" x 11.8" x 11.8" Landan Nano Cube (Amazon) in which I wanted a small heater that couldn't be seen. ALL the small heaters I tried were failures at maintaining the status quo temp I was seeking. They couldn't hold 78°F water temp. no matter how small the aquarium / bowl. So I had this big-ass honkin' heater in my 11.8" cube and THAT did a great job but too bad it's HUGE and is easily seen as a big ass THINGY in my cube. I stopped heating the bowl. The little Nano heaters I was buying for the bowl couldn't even maintain my bowl temp. and that was my small bowl at about 2.5-3 gals. Now I just bought the larger 4 gallon bowl and it LOOKS Huge but still small relative to the cube. So I'm thinking...I better look HARDER for a good mini-heater and I landed on this PULACO 25W heater. One of my criteria for buying on Amazon are the reviews. Not just written review content but HOW MANY reviews the item has. The PULACO 25W heater has over 10,500+ reviews! WHAT!? Now, I'm interested! It's PRE-SET to 78°F so that's what I want in my Nano and my bowl. If you have a situation where you are keeping animals or plants where you want it warmer or cooler i.e. you don't want 78°F. Then this is NOT the heater for you. Seventy-Eight Degrees. That's it. But it's a reliable 78°F and I check it regularly two different ways. You will actually receive a small 'Stick On The Side' thermometer which I stuck on the Nano side wall. I also bought an Etekcity Infrared Temp Gun (Amazon) which I take temps of everything. I heat replacement water for my Nano tank up to the current temp and I'm taking their temps with the Infrared gun. Both the cheap 'stick on' sticker and the Infrared gun confirm---> 78°F !!!! I was shocked and surprised that this little guy...the PULACO 25W Small Aquarium Betta Heater with Free Thermometer Strip did EXACTLY what it was advertised to do. Heats water up to 78°F and holds it steady at that temp. I even experimented by using it for a week in the 7 gal. Nano and it held 78°F as advertised. So, despite it's diminutive size which I LOVE LOVE LOVE it's only supposed to be rated up to 6 gallons. To be honest, my Nano probably has 6 gal. in it once I subtract the substrate, the hardscape, the plants, etc. Anyway this little PULACO 25W is also a PLUG 'N PLAY. All you do is plug it in! It's easy to use and you can easily hide it for your viewing pleasure! I just want to comment on the negative reviews. I know that there is mixed feedback on durability, performance, quality heating value (whatever the definition of THAT is!) but I have not had an issue and I've been using the hell out of it for two months. I don't understand the complaints about glass breaking? Now, I haven't been rough with this PULACO 25W glass heater, I haven't bumped it against the aquarium or bowl. I believe that ALL GLASS HEATERS are prone to breakage (especially if you have some age on that glass heater!) and YES, I believe you could break this little PULACO with the wrong move (glass is breakable!) but I find it hard to believe that the glass would break with normal use. Just sayin'...how do you break a glass aquarium heater? It doesn't take much imagination to picture it breaking...now picture HOW it got broken. Another interesting aspect of this heater is that on my little 11.8" cube (about 6 gals) I am running not one, but TWO EHEIM Canister filters. Both are the small EHEIMs (Filter 2211 -'Classic 150') but still... I am moving a LOT of water using two EHEIM Canisters on that little cube but that little PULACO 25W handles it, keeping the water at 78°F even though I am moving so much water through the two canisters. I think that it's not only interesting but important to know that the little heater is a solid choice. LAST BUT NOT LEAST----> remember my headline? SATISFACTION GUARANTEED! Here is your promise from the manufacturer: ★【SATISFACTION GUARANTEED】Our Aquarium Heater is built with durability in mind and safety for every design. In the remote possibility that you’re not satisfied with our product, just contact us, and we will gladly give you a new Aquarium Heater replacement. 12 Month Warranty and 24 Hour Professional After-sales Service. And, of course, if you find that you don't like it right away, return to Amazon for your refund. And NO, I don't work for the PULACO people in any way, shape, or form. Out of all the crap I buy on Amazon, I write this because it's a product that I believe in and I have run the gamut of small heaters, all the rest failures. ... show more
Reviewed in the United States on July 2, 2024 by Bobby Magic

  • Very efficient
Model: 25W
This heater works great! I have it in a 3 gallon tank for quarantine and I also have it in a 16 gallon tank and still works! I monitor the water temperature everyday just for good measure. I have also found that in the summer, I don't use it as much because the tank stays warm naturally and I don't want to overheat my tank. Where I live gets really hot up to the 3 digits. In the spring, I find these very useful as it really regulates the water and keeps it between 76F and 78F and I think my tank is oversized for this heater because it states that it's for under 6 gallon only but it still works in my 16 gal tank. It's easy to know when it's working because it turns from red to green when it reaches the right temperature. It's small and doesn't take too much space. My Pleco and other fish likes to stay around it and it doesn't hurt them even when they get close to it. I will probably upgrade to a bigger one when winter comes for my large tank. I don't want to overwork the heater but for now that it doesn't get cold in my area it works perfectly. It's so efficient that I ended up buying two of them. I highly recommend it! ... show more
Reviewed in the United States on May 28, 2025 by MiniAmi

  • Great for betta tank
Model: 25W
Works great with keeping Blue the betta’s water at the perfect temp for him. Suction is good. It is a quality water heater. As you see in the pictures,it will turn red when the temp of the water drops and green once it is back to the temperature it needs to be at.
Reviewed in the United States on June 9, 2025 by terryn green terryn green

  • Great Heater, Thermometer doesn't work at all
Model: 25W
The heater does exactly what it should. It keeps my 5.5 gallon tank right at 78 degrees F. I installed it horizontal about an inch off the substrate in the back of the tank and my betta loves hanging around it. It's a little worrisome, but I figure he knows what's best for him. ?? The thermometer that sticks to the outside of the tank doesn't work at all. I left it for a week and it never displayed a temp. I bought a suction thermometer that goes on the inside of the tank. I put it on one of the sides and it verifies my temp is always 78. Overall, very happy with the purchase. ... show more
Reviewed in the United States on May 15, 2023 by Vicki Apple

  • Going strong 3 months in!
Model: 25W
I’ve been using this in a 5 gallon beta tank for a few months now and I haven’t had any issues! The temperature is pretty consistent and it’s a great heater for what you pay. I’ve had tons of issues with heaters not suctions properly to the sides of tanks but this hasn’t moved at all! The light is a little bright on it but we keep our tank in the living room. I would definitely recommend it! ... show more
Reviewed in the United States on May 16, 2025 by jillian

  • No complaints!
Model: 25W
Easy to install and has kept the tank’s water at a steady 78 degrees F!
Reviewed in the United States on July 15, 2025 by JenCamp

  • Works perfectly to hold temperature.
Model: 25W
It hold the recommended 78 degree temp. perfectly without having to adjust. Works perfectly at such a low cost.
Reviewed in the United States on June 28, 2025 by Donald K. Moeser

  • Recommended For Warmer Climates
Model: 25W
This heater never a actually reached 78 degrees. It always hung around the 76 degree mark verified by an additional thermometer. Switched out to an adjustable heater and that one actually hit the temperature I set it to. Verified by multiple thermometers. I think this would work better for an aquarium between the 1-4 gallon range and no more. ... show more
Reviewed in the United States on June 16, 2025 by Hanners

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