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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: 20 left in stock
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Arrives Feb 10 – Feb 17
Order within 2 hours and 37 minutes
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Model: 25 Watt-Under 6 gallon


Features

  • Betta HeaterThis 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 GUARANTEEDOur 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: Waterproof


Color: Black


Age Range (Description): Adult


Included Components: Heater and Thermometer Strip


Outer Material: Glass


Specification Met: CE


Display Type: Analog


Product Care Instructions: 100% submerged into water


Unit Count: 1 Count


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


Item model number ‏ : ‎ 25 Watt-Under 6 gallon


Date First Available ‏ : ‎ November 18, 2019


Manufacturer ‏ : ‎ PULACO


Country of Origin ‏ : ‎ China


Best Sellers Rank: #2,796 in Pet Supplies (See Top 100 in Pet Supplies) #5 in Aquarium Heaters


#5 in Aquarium Heaters:


Customer Reviews: 4.3 4.3 out of 5 stars 11,022 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Feb 10 – Feb 17

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


  • Works great!
Model: 25 Watt-Under 6 gallon
I needed a heater for my betta tank since it's getting colder and this was perfect! It was really easy to install (literally just plug it in and suction cup it below the water level) and keeps the tank water slightly above room temp which is perfect for my fish. I would keep in mind it has a SET temperature of 78 degrees which you cannot change! The reviews of it overheating and "cooking" people's pets scared me, but I just watched it like a hawk the first day I installed it to make sure I didn't get a faulty one. I've never had an issue! Well worth the price:) ... show more
Reviewed in the United States on November 16, 2024 by Ruthie

  • SATISFACTION GUARANTEED!
Model: 25 Watt-Under 6 gallon
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

  • Perfect for small guppy tank
Model: 25 Watt-Under 6 gallon
Our other heater needed the top to be out of the water for it to work, and when it fell completely in, the heater died and allowed the water to be too cold and killed one of our fish. This was the replacement and it works amazing. I especially love that it needs to be fully submerged to work, so no chance for a mishap like our other one. It comes with a thermometer sticker to put on the inside of the tank for extra reassurance of the water temperature. This heater really is a plug it in and forget about it product. I recommend! ... show more
Reviewed in the United States on November 21, 2024 by AHyde

  • Great Heater, Thermometer doesn't work at all
Model: 25 Watt-Under 6 gallon
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

  • Maintains perfect preset temp on 6 gallon tank
Model: 25 Watt-Under 6 gallon
This heater has worked perfectly in my 6 gallon tank. It keeps the temperature right around a constant 78.5 for me. The room is kept between 67-72 degrees. I monitor it with a digital probe (which I tested for accuracy separately). My betta is very pleased. It was cheap and I will probably replace it after maximum 2 years or sooner if needed, since aquarium heaters do wear out and have a life span. This is great heater size and right wattage for the aqueon 6 gallon frameless tank. The running light can be annoying if the tank is in your bedroom (but that's my fault haha). ... show more
Reviewed in the United States on October 25, 2024 by MrsW MrsW

  • On a tropical vacation!
Model: 50 Watt for 6-10 gallon tank
I teach in building where the HVAC is always busted, and it gets cold. But I don't worry about our classroom fish; they are nice and toasty at 78 degrees. The heater was easy to install, well-made, and easy to use i.e. one button.
Reviewed in the United States on December 14, 2024 by Pokemon Lover

  • Works like it is supposed to
Model: 50 Watt for 6-10 gallon tank
Easy to set up and get going. Does not take up a lot of space in a tank. Works and functions well.
Reviewed in the United States on November 27, 2024 by Tanner

  • The little heater that didn’t
Model: 25 Watt-Under 6 gallon
So I guess I read the description too fast, I thought it was rated for a 6gal, but it actually says UNDER 6 gal. But hear me out, this thing has a light in it that turns red when it’s heating and green while it isn’t. It’s almost ALWAYS green. So, I feel like it’s actually just not keeping my 6gal at the correct temp. If it were trying, and failing, to keep the “too large” tank at the correct temp, the light wouldn’t be green all the time. It’s keeping my 6gal at a steady 76/77, not warm enough so I ordered a 50 watt from a different brand with controls to adjust the temp. So, if you have a 6gal, go with a 50w heater. ... show more
Reviewed in the United States on November 27, 2024 by StephE

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