Aqueon Aquarium Fish Tank Heater, Preset, Up to 30 Gallons, 100 Watts | 30 gallon aquarium heater, fully submersible with auto shut-off, preset 78° and shatter-resistant quartz glass

Constantly running on a 20 gallon mixed reef tank for the past 11 months as a backup secondary heater and worked great. I removed my main heater to for a few hours for maintenance and let this preset heater in the tank only. I noticed the temperature drop to below 75 degrees f (almost 3+ degrees below preset of 78). Contacted Aqueon as it is still under warranty and now they are sending me a replacement unit. Great customer service, too.

This is a good heater, but have had a couple issues. This is my second one. The first one worked great, but after a few months, it stopped working. I ordered a new one, and this one keeps shutting off even though the water isn't that warm. Maybe it's on purpose, because it shuts off around 80 degrees, but I swear the first one heated warmer. My ideal would be about 82 degrees.

Very pleased. I’d always thought aquarium heaters would be expensive and for very serious, high-budget aquarium aficionados. I’m thrilled that I can offer a little heater to my betta! I was worried about his water becoming too cold in winter. Now I can keep his tank warm without worrying about the overall room temperature. Great buy! I don’t love the look, but once you’re used to it, it’s just part of the tank. The alternative is to heat the entire room to temperature at all times, which is just unnecessary, so the aesthetic tradeoff is worth it.

Aqueon is a trusted brand in the aquarium industry. This heater is very convenient because it is preset and has safety features built in. I bought it to maintain temperature in my betta fish tanks but came to find out that it only works correctly if your home is warm enough. To elaborate, the ambient temperature of your house needs to be 73 in order to get your tank to 78. I did not know this before I bought several of these and therefore, my tanks are not at the desired temperature. I feel that this is a design flaw or oversight and really wish that the brand would correct this. How many people really heat their houses to 73 in the winter? Unfortunately, I am unable to heat my house more than 65 degrees. I still use this heater anyway but my betta fish is not living in optimal conditions due to the way the heater was designed. If your house is above 73, I highly recommend this heater. Aqueon makes great products.

Anything from Aqueon seems to work well and last a long time. I needed a new aquarium heater after 8 years with the original one. I don't think that's too bad after being in water for that long! So I ordered the same one again. My fish are happy!

I thought was good heater, perfect for small tank. In September 2023 1st purchase for 20 gal tank, then bought another for 5 gal tank. No problem for first couple weeks. They worked straight out of the box, then I noticed they were both not maintaining the temp. This morning (10.12.23) both not heating. 20 gal Tank temp down to 73 degrees and heater off, second heater also not on 5 gal tank has 74 degrees, again heater off. Both unacceptable for the tropical fish which require temps at 78 degrees or higher. I unplugged and replugged - that made them both come on, but neither would not stay on. They are completely submerged. Have made steps to return one, but the other is just out of time to return. Both the heaters will come on when unplugged and replugged but fail to stay on to raise tank temp to correct temp. Very disappointing because they are pefect size and 78 degrees is the correct temp. I was lucky to have a backup heater for one tank.

Works excellent. Actually use it in our chicken waterer to keep it from freezing.

This heater is fine provided you are ok with it being off the rated 78*F a slight bit. Mine kicks in at 77* and then the red light goes on and it holds steady at 77*F in a 20 long and rarely lights to maintain temp. Even though my room temp was 73*, my LED tank lights were high enough to make it never actually light until I tested with ice cubes and a thermometer. It's liertally half the size of the top rated German 100 watt which won't even fit well anywhere but the back and the black and small size makes it blend well in a planted with dark substrate. Long term reliability is iffy at under $15 based on Utube vids but so far, I am very happy. Only a 6 footish cord, so you may need an extension from the outlet, especially to place it low and horizontally.

I was shocked about how good this item is. When it first came, I thought it would overheat my tank, but I had to give it a try. So when I placed the heater in, the suction was pretty secure! I was surprised by this, because lots of heaters' suction power does not stick well. It gets better and better! I turned on the heater and I saw the red light. I waited for a few more minutes and the light went down. At first, I thought I didn't plug the cable well, but after a while, I realized it was actually controlling the temperature in the tank. Amazing! It turned on and off, on and off. Then I checked the temperature in the tank. It was perfect! Overall, this heater is a solid 5 star!

Excelente calidad. Funciona perfectamente. Mantiene la temperatura ente 24 y 25 grados. Lo uso en un acuario de 60lts

I have 2 of these heaters in my 30 gallon tank just in case one goes out. Reliable, not a problem since.

Buen producto, marca me gusta mucho, llegó en buen estado y funcionando bien

me parebe bueno para el precio, cumple bien su funcion.