AquaMiracle Adjustable 10W Betta Heater Small Aquarium Heater Submersible Fish Tank Heater 5V/2A USB Powered Super Mini Aquarium Heater with Digital Display Thermostat, for up to 1 Gallon Tanks

The media could not be loaded. I absolutely love this little heater! It’s the perfect size for my betta tank, and it does exactly what it promises. The adjustable temperature feature is spot-on, and it holds the temperature consistently without any fluctuations. I was pleasantly surprised by how reliable it is for such a compact heater. It’s discreet, easy to install, and doesn’t take up much space in the tank. If you’re looking for an affordable and efficient heater for your betta or small aquarium, this is definitely the one! I’ve attached a video showing how well it works in my tank.

Sam, our unexpected Betta fish birthday gift for our 7-year-old, quickly became a beloved member of our family. To ensure his happiness and comfort in his new home, we had to learn the ropes of Betta care. It was surprising to discover that these little fish, often sold in deli containers at pet stores, require a considerable amount of care. During our research, we learned that Betta fish thrive in water temperatures between 78 to 82 degrees Fahrenheit, and achieving this meant we needed 5 watts of heating power per gallon. That's why we found the 20-watt heater to be a perfect match for our 4-gallon tank.This compact heater was an ideal solution for our uniquely shaped round tank, where our only option was a fully submersible heater. Many other models we came across were bulky and had no suitable attachment points. However, this heater's strong suction cup allowed us to discreetly position it near the rim of the tank, preserving the tank's aesthetics. Not only has it maintained a consistent water temperature of a perfect 80 degrees, but it's also safe to touch, as Sam often swims close to it without harm.One feature we appreciate is the easily visible digital display, which helps us monitor the temperature and ensure Sam's safety. However, my one concern is the auto-shutoff setting, which is set at a rather high 97 degrees. Knowing that Bettas cannot survive in water temperatures exceeding 86 degrees, I can't help but worry about the possibility of returning home to an overheated tank.

First heating element would not read temperature, change settings, etc. Company sent a replacement that arrived the day following my request. It appears to be functioning great, just reads a lower temperature by five degrees or so according to my thermometer.

I got my first of these Heaters near a month ago for my 1gal. Betta bowl. Nifty (neat and easy to use), it's been a perfect fit for the compact bowl space, with a digital control combining thermostat (to set the desired heater temp) and thermometer (to show the actual aquarium temp).Loved it so much, I then got a second one, this for my cylindrical 2gal. community tank which is home to six Guppy/Molly/Platy fishes. Yes, it is overcrowded but I closely monitor the tank's water quality and other parameters as well as the fish behavior there. And all the guys are doing well, as shown by their feeding habits, mobility, even schooling activity.Relying on these Heaters for keeping both of my minimal aquaria at an optimal 80°F I've felt confident that all is well. Until the last day or two… my apartment has cooled somewhat from its usual 75°F or so down to 68°F, nothing drastic. Yet the two heaters now seemed taxed to hold their spaces at the 80°F I've set. Each aquarium now hovers at 74°F, shown by the controls of each heater and verified by strip thermometers, one on each aquarium located up against the heater (at least for the Betta bowl). This is a mildly troubling issue on which I will update this review if warranted.

Bought the 30w heater for my 6 gallon cube. I had it set to 76 while I was cycling the tank. Put a thermometer into my tank after 2 weeks and it read 72 degrees. So I assume that it's just inaccurate and raised the set point to 86 degrees. Guess where that got me after 30 hours? You're right! 74 whole degrees! You know what the ambient temperature in my house is? You guessed it! 74 degrees! This thing can't even take the 6 gallon nano cube over ambient temperature? Or should easily be able to atleast keep it 5 degrees warmer than my house. Waste of money, I don't suggest buying this. The built in thermostat on it it says it's at 82.5 degrees but the tank is at 74 degrees i have to throw an a 50w heater in now.I had high hopes because I really wanted something easy to hide in my nano tank, no I get to slap a huge 50w heater in there in complete disappointment. I can't even send it back because I'm past the return window now. But I don't even think this 30w heater could maintain a 3 gallon tank.Manufacturer feel free to get in contact with me about your worthless product. Either you have absolutely no quality control/testing or your just pushing a product that you know is garbage and won't work right. I usually ignore bad reviews when I read them but everyone else with the same issue is spot on.

Works well for my little 2.5 gallon nano tank that I use for a beta and plant. And that it is digitally adjustable makes it even better. Also comes with a suction cup clip to attach inside your tank. Don't expect major temp changes but it will adjust up a few degrees in 5 gallon or smaller tanks. The heating glass is exposed so be sure your fish/snails/shrimp/critters can easily get away from it's glass if it kicks on when they are attached to it.Nice little heater that's easy to setup and use with big temp numbers you can see from across a room.For very small tanks only.

Warms up my 2 gallon tank.