DaToo Mini Aquarium Heater 25W Small Fish Tank Heater 25 Watt with Free Thermometer Sticker

Have had it plugged in and running for a few days in my 1.5-gallon tank, and it is working great! The red light turns on when heating; green light when it's at temperature (~78° F), which I've been monitoring via a digital thermometer (temperature seems to stay right between 77.5° and 78.5°). I'm not able to adjust the temperature, but 78° is right around the temperature I'll be needing, anyhow. This heater keeps the temperature in the target range, whereas the 10W heater that came with the tank couldn't, as the water was always way too cold previously. The included thermal tape thermometer kind of works, but is not very accurate and it's really hard to discern the colors; it's nice to have, but I'd recommend something else if you need more temperature accuracy than ±5° and you have a larger tank or a colder room. Also, the suction cup fits the heater well and is nice and soft, holding to the plastic tank really well! (I was a little impressed with that, actually.)

It’s a nice size, works very well. It looks good, sticks well to the inside of the tank. I’ve had it for 4-5 months and I’m glad I bought it. It’s a preset temperature so you don’t have to worry about that. A must have for a smaller betta fish tank. 10/10

Works really well for a 2.5 gallon aquarium. Keeps a steady temperature. Great value for the price!

I have ordered a ton of these. So far, most of them seem to work pretty well. They keep the tanks around 78F, give or take a tiny bit. You can’t adjust the temperature since it’s preset. I’d like it if they came in a smaller size and also if they had a shatter proof option. These are glass without an outer casing so they might shatter if they overheat. These are not mini but they’re not huge. They’ll work for a 5 gallon tank or bigger. Don’t use these in anything under 5 gallons. They’re too big for that and might overheat. The heaters are easy to use. Just attach the suction cup, place in tank under water, and plug them in.

Great heater. Bought it in a hurry without much research and I'm really happy with it. I have it in a 5 gallon tank and it keeps it at around 74-78 for the most part. It fits in the back of my tank well so it is concealed, keeps it at an even regular temp even with our house temps fluctuating, and I've had no issues with it. Easy to use just plug and go.

I'm using this for a 3-gallon shrimp tank. It's tiny. It's cute. There is a very belt-and-suspenders approach to being sure this thing is working properly. It lights a little even when it's not heating the water (I expect it's not heating the water when the room is nearly 90 degrees in August). The light is really only visible when the tank is dark and there isn't too much light in the room, but it's a small square by the bottom, just to clearly indicate it is working. I like that assurance. The little thermometer, which is also tiny and out of the way, would be another indicator, again if it weren't August and showing the water temperature in the 80s without the heater. So you can be certain, if there is a problem, you will know. But the ambient room temperature does lead to another point. It's small and I don't think it's that powerful. For me, the room is never going below 70 degrees. I'm in an apartment building with a lot of elderly residents, and the super needs to keep the place warm bordering on hot for them. I need the heater. The water will get too cold for the shrimp without it. But not more than say 10 degrees below their comfort level. If you're thinking a tank in say a garage (I know some people who use that as an office and keep a betta there) and you're prone to reasonably cold winters, then this might not be the thermometer for you. The shrimp seem to think it's a nice platform to sit on. I usually find at least one perched on top. I like especially how deep I can store it and the suction cups keep it firmly in place. If I'm only doing a one gallon water change (they're shrimp -- they have a really low bioload so changing a gallon a week is fine) then I can keep it plugged in while doing the water change and it stays fully submerged the entire time.

Though given some of the other reviews, I am extremely happy with this heater. I've had it installed for about 3 weeks. Temp is staying a solid 77° F. The suction cup isn't the strongest, but it's worked OK. Value for price was very good. I worry about its long-term durability, but so far A+++.

im new to these types of set ups but this has never failed to show up this tank heats it like nothing and it cools down as well. I have no worries

Excelente, mi pecera es de un galón y aunque hace bastante frío los peces están a buena temperatura

Probably my fault more than the product's but this heater is only suitable for quite small tanks. It was working hard to keep a 5.5 gallon tank to temperature. I know if it's on more than it's off that it will shorten the life of the heater. It has now found a home in a 2.5 gallon tank with neocaridina shrimp in it. I just didn't know enough when I bought it and thought it would be okay for a larger tank. I have learned to buy more watts than you need as the heater won't have to work so hard.

No sirve la verdad no funciona

DaToo Mini Aquarium Heater 25W Small Fish Tank Heater is a good small heater for aquariums. I bought it a long time ago and it is still working well. It’s compact, easy to use, and does what it is supposed to do. Overall, a reliable option for small fish tanks.