Mairubys rondon—March 7, 2026✓ Verified purchase
Igot this mini USB aquarium heater for my tank, and it works really well. It’s small and adjustable, so I can set the right temperature for my fish easily. It’s convenient to use with USB power, and even though it’s compact, it heats the water quickly and keeps it stable. Very practical for a small tank, and my fish seem happy and comfortable. Read more
Alexis—July 8, 2024✓ Verified purchase
Won’t turn on after abt maybe 30 mins of using it at the temp of 78. Fish tank cold again. Very upset. No power to it at all. Not happy Edit- They sent me a replacement heater & I received it in a day. I went to go wrap up the old one that didn’t work n burnt my finger….so….apparently that one IS working but didn’t for days…? idk I tried it for days w the heater in the water n it wld not turn on. Took it out of the water now to pack it up etc, unplugged it, grabbed the new one to set that one up and when I grabbed it the heater was burning hot. Huh. So I plugged that one bck in and what do u know…. Digital screen wrkg, all is well. Idk. I still packed that one up to send bck obvy bc I don’t want to hurt my lil fishy if it’s malfunctioning. I appreciate they sent me a new one so quickly!! And will see how this one goes!!! ((This lil guy was a “surprise for my son by my niece so this is obvy his temp home until I can order a larger Fishtank for him n toss this one out lol can’t imagine drinking lemonade from it again……..)) Read more

Shay—December 1, 2025✓ Verified purchase
It worked fine/normally for about a day. It does heat, but it's not automatic, and setting the temperature does nothing. I've tried unplugging, replugging, powering on and off, etc. and it doesn't get better. Each time it's reset it works fine, but slowly starts detecting the temperature as higher and higher until it reaches 98 F, and then it stops. Because it thinks the temp is 98 (it's not) it doesn't actually turn on the heat unless you manually reset it Read more
Mari—December 2, 2025✓ Verified purchase
Works well in stabilizing the aquarium temperature. Fits inside the 2.5 gallon aquarium easily, however the suction cup is too weak to hold it in place at all times. I would recommend as a good value for the money. Read more
Customer—March 10, 2026✓ Verified purchase
I bought 2 and the 1st one does not work, haven't tried the second yet. It shows the temp of the water to be about 69 degrees when I plug it in, its set at 79 degrees. So the numbers start going up from 69, and keeps going up to 90, even though its set at 79, but it not really at 90, you can unplug it and plug it back in and it goes back to around 70. It thinks its 90 degrees in the tank when it is not. Edit: it works on Celsius only Read more
Ron Anderson—December 4, 2025✓ Verified purchase
I got this for a mini tank that I use to raise brine shrimp. I needed a small heater that was easy to set and didn't take up much room. I put this in my tank and it immediately started heating up my tank. It was easy to set and the readout tells you the current water temp and when the heater is on. I love it is USB so that I can plug it into my hub and not have to use up and outlet. I also like it uses so little power to run so it will be a lot more efficient. It looks well made and has been holding the temp where I need it. I didn't use the suction cup that was included and just let it settle to the bottom of the tank where it sits without an issue. The suction cup it comes with is a nice one and not like some cheap ones I have got in the past. Read more
Tiffany Hall—August 13, 2025✓ Verified purchase
Perfect size for a .75 gal to 5 gal betta tank. I put it in my .75 betta tank and it works perfectly. It doesn't make the water too hot, the glass is durable, and for the price, I feel I got the bang I was looking for. Read more
Ka—February 4, 2025✓ Verified purchase
My lesson: Don't buy glass heaters for aquariums again. This is twice, so shame on me. (A previous 25watt glass heater I bought from a different seller was nicked somewhere and the crack that formed caused a messy failure of its own. It was a Different brand of heater, and again, Different Seller on that one.) This little heater broke but possibly through no fault of it's own. It's a thin glass bulb that I believe could actually be a bit thicker. What happened in my case is the bulb bumped the aquarium glass and it was enough to break it open. This sent broken glass and the sand-like particles to the bottom of the tank. All livestock in my aquarium had to go through an emergency transfer to avoid broken glass and possible contaminated water. The livestock is about 60 two-week-old baby snails I've bred. Three to four of them did not survive the ordeal. I got the tiny heater specifically to keep the gallon and a half of water just warm enough for the babies to thrive and be comfy. My biggest dislike is this being powered by USB. Yes it's a cool idea, but you have to remember this is a heater. Don't plug it into a USB HUB with other electronics. My lamp dimmed, and stayed dim each time the heater kicked on when I used a USB HUB, so that should give you an idea of the power draw that's happening off and on. Everything plugged into that UBS HUB is experiencing the same thing as the light. When using a USB wall plug adapter with the heater, the adapter still gets very warm to the touch (I tried a few). To me, this just isn't a good thing. Knowing I don't have issues with other, larger heaters, it isn't my electrical in my home. Nothing else I own that is USB powered makes the adapter that hot, so I would just use caution with this one. I am bummed bc I really do like the idea of this product, and bc of course I have to get another heater. The way this heater is powered is the main reason for the rating as safety is paramount, for you and your wet pets. The thinness of the glass bulb is something that if improved, would make this product better. Read more