Fluval M 50-Watt Submersible Aquarium Heater for Fresh & Saltwater Tanks

I love this heater. I have been using it in my betta's tank for about a year, and so far, it has worked very well! This heater is not made for being completely submerged under water. The black and grey part (the part above the little wavy marks) must be above water, along with the cord. I put this heater right next to my filter so that the filter motor can move the warmed water around the aquarium evenly. This heater is, of course, automatic. It has a thermostat somewhere in it that tells it to turn on when the water is too cool and turn off when the water gets warm enough. When the heater is warming your tank water, there will be a blue light on the side, and when it turns on and off, it will make a clicking sound and the light will turn on or off. This is a very good heater for my five-gallon tank. I have it set at about 81 degrees, and it keeps my tank at a steady 78 or 79 degrees Fahrenheit (which is the perfect temperature for betta fish). I am very impressed!

So I went through and looked at all the 50W's heater reviews and only about two of maybe twelve were negative or lower than four, so I went for it and bought it. I tend to go for ViaAqua, and for most all my tanks have their glass heaters (in 50W and 200W). I didn't for this tank in part because the price went up for the ViaAqua heater I normally get for 5g tanks, and I splurged and got the Fluval Chi and figured I may as well keep with all one brand for this tank. I don't think it has to go on very much, save for maybe at night, but in winter I'm sure it will be used much more. It is an attractive heater, I suppose - looks nice in the tank for a heater. It isn't really invisible, though it isn't as visible as some people said it was. I never needed it to blend in with the tank, so I didn't really care if it was or wasn't visible. I think because I have a Fluval tank it is less visible (they are really reflective, I guess, so if you don't have plants that go too high in it, then I think it probably blends in better). If I have any issues with it, I'll edit this, but I think because it is a fairly low power heater, it won't be too much of a problem. A lot of the negative reviews this product got was for a different size (the 300W and 200W ones, I think).

Accurate to one tenth of a degree. Super stable even with my ac blowing on the ten gallon shrimp tank. Bigger in length than the one in my twenty gallon but a lot better than the Penn Plax 50w it replaced. I have it mounted sideways despite the manual saying not to. Everyone says it is better sideways and they are right. This brand is my go to going forward. Highly recommended.

Espectacular, calentador para pecera. Tipo espejo se escamufla con el hábitat de tu pecera y cumple con su función muy bien autorregulable. Para poder poner la temperatura ideal, es muy bueno

First, I selected 2 days shipping through Amazon Prime and received this item exactly on time, in the afternoon of the second day. It was packaged in a box with bags of air. I appreciated that since this is a fragile product. The first thing I noticed upon opening the box was that this heater is huge for the wattage. Mine is 50 watts, to be used in a 10 gallon aquarium, and it is almost exactly the same height as the aquarium itself. Then when I put it in the aquarium it became clear that the reflective surface of the heater serves only to make it MORE visible. It just looks like this gleaming shiny metal object in there, and doesn't really seem to actually reflect the colors surrounding it, but instead it reflects the aquarium light above. Because of this I decided to lay it against the bottom back of the aquarium so that it is obscured by plants, and the cord goes right up the seam of the aquarium where it isn't noticeable. If you're buying this for its subtlety, you'll be disappointed. BUT, despite this, I am pleased with my purchase to far. It has been keeping my 10 gallon betta tank appropriately warm, within a degree of the setting and that's all I really care about. I was going to get a Hydor Theo but this was bit cheaper. It seems to perform just as well. Granted I have only had it for about a day and a half, but I will update my review if the performance changes. In case anyone's wondering, the heater appears to be some sort of metal or metallic material encased in glass, so it is fragile like other glass heaters. It's not made of metal on the outside. Finally, I wanted to dispel the myth that this heater is not fully submersible. Although there is a fill line on the heater, my research has shown that everyone who has called the company directly has been told that the heater can be fully submerged safely, and that the fill line was included only due to some sort of strange government regulation. ---------------------------------------------------------------------------------------------------------------------------- Thought I would edit and say this is still heating well for me. I've also moved it into a different tank, and was able to position it in such a way that it is not very visible. I'm uploading a picture for reference.

I have a constant temp recorder and it shows this heater regulates my 9gal tank to the +/- 0.1 deg F. Worth every penny

Good heater never had issues.

I'm not a fan. It appears to be a Metal Cased heater, but it's made of glass. The metallic look is due to a reflective insert on the inside of the heater. This insert is to give a reflective look for in-display placement. The mounting clip is cheaply made and doesn't secure the heater, nor the suction cups. I now have a rouge suction cup in the heater section of my Fluval Flex that I can't retrieve nor attach the bracket to.. The heater tends to fall off of the bracket quite easily. The temperature control is ambiguous. The settings are 66, 72, 75, 81, 86 with a singe "|" marking to the left and right of the number. What do these numbers indicate. I want my tank at 78. Do I just guess? I don't feel like I've got what I paid for. The Eheim heater has better construction, a more detailed temp control and the quality is far superior.

Calienta bien y de buen material

This is an amazing heater, I’ve gone through probably 5 different brands of other heaters that won’t keep a consistent temperature or won’t even work in general. Saw a recommendation for this brand/model and I love it! Super easy to use and to adjust temperature. Highly recommend

Très bon chauffage, aucun regret sur son efficacité

Toller Heizstab! Kann ganz unter Wasser gesteckt werden. Schaltet ab und an den Sensor ein, um die Temperatur zu überprüfen. Seit einem Monat im Gebrauch und die Temperatur bleibt konstant. Gut verarbeitet.

Utilizo num aquário com 3 pequenas jovens tartarugas...correto grau de temperatura em relação ao escolhido...pode ser considerado excessivo para o meu pequeno aquário 40x20x17), mas cansei-me de comprar outros mais baratos, com tamanho menor, mas que tinham problemas com a efetiva temperatura da água: divergências quanto a graus de temperatura da água e a selecionada/indicada