- 25Watt Mini Aquarium Submersible Betta Heater with Free Thermometer Strip for 1-6 Gallon Fish Tanks (Preset Temperature 78℉)

Our family got a betta fish and, like many new fish owners, we were very excited to create what seemed like the perfect little home. Nice tank, clean water, decorations, carefully chosen spot in the house, everything looked great. Unfortunately, the betta looked less impressed. He spent most of his time lying limp on whatever surface was closest, looking like he was quietly preparing to leave this world despite all our efforts. It turns out that New Mexico winters do, in fact, get cold, and the room we had the tank in was apparently not ideal for a fish with tropical expectations. We added this small submersible heater, and almost overnight we had an entirely different fish. Suddenly he was colorful, flashy, swimming around dramatically, and acting exactly like the stereotypical betta fish we thought we had purchased in the first place. Highly recommended! Apparently all he needed was warm water and an attitude adjustment

This little aquarium heater works great for my betta tank! It heats the water consistently and keeps the temperature stable without taking up too much space. Super easy to set up and completely submersible which makes it nice and clean looking in the tank. The only reason I bought it was for a smaller setup and it has been perfect so far. Great value for the price and my fish seems much happier now!

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!

Not the greatest mini heater, but cheap enough that I got what I expected out of it. It lasted about a year before it crapped out on me. During that time, though, it worked very well, maintaining a consistent temperature in a 5 gallon mini tank for the full year with barely any maintenance. What eventually happened was that the glass housing separated from the rubber on top and it became waterlogged, which ruined the electrical components. It no longer worked at all after that and I just chucked it in the trash. For just ten bucks (I think that’s how much I paid for it), I don’t consider it a big loss, however

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.

I bought this heater because it was explicitly advertised as being safe for Betta fish. It is not. This heater overheated my tank and murdered my Betta. The tank size was appropriate, the heater was fully submerged, and I followed the instructions exactly. The temperature climbed far beyond a safe range, and by the time I caught it, the damage was done. What makes this worse is that after my fish died, I read further down the reviews. At first glance, the reviews look fine. But if you actually read past the top few, it is the same story over and over. Overheating. No temperature control. Dead fish. I usually do a good job reading reviews, and I regret trusting the “Betta safe” labeling on this product. A heater marketed for Betta fish should be one of the safest pieces of equipment you can buy. Instead, this product creates a lethal environment. A heater without reliable temperature regulation is not just defective, it is dangerous. Amazon should do something about this. This product should not be sold as Betta safe, and at a minimum, Amazon should refund or replace not only the heater but also the cost of the fish it killed. If you care about your fish, do not buy this heater.

Works perfectly! Great for tropical fish

Good heater, replaced 2x because i dropped it and it shattered everywhere so easy to break, good for the money, and if your careful with it then its great

Muy bueno, ya tiene dos años y sigue sin problema alguno.

Keeps the aquarium at a perfect temperature for my betta, keeping him comfortable and happy.

Never expected this. It has mentioned prefixed temperature at 78F. I installed on my tank in the night By morning the heater has malfunctioned and burnt my Betta fish and money plant. Heater was immersed properly- because of overheating- there was evaporation and water loss

Connected it before 6 hours, heated the tank only once at the beginning up to the point and after that temperature is just dropping and dropping. Red light is on from the beginning. I've even touched it to feel if it is warm but not at all.

El calentador es efeciente y funciona de maravilla en nuestro acuario de 3.6 galones.