FREESEA Aquarium Fish Tank Heater: 50W Small Submersible Turtle Heater with Adjustable Temperature External Controller for Betta | Saltwater | Freshwater | 1-10 Gallon

Heater works well and is very efficient. I have a 5gal Betta tank with some live plants and betta in it. Its an office tank and set up with plants that would tolerate not being heated. Since setting up the tank I moved into a new position and part of new my office is exposed brick walI, which makes it harder to maintain the temperature. I was looking for something smaller since my tank is small and prefer submerging heaters. I also didn't want to spend a ton of money on it if possible. Since adding this I have noticed my betta is more active and the plants are growing much quicker. Temperature rises quickly to setting and maintains steadily with no adjusting from me. The only negative I would have would be that every 3 or 4 days the thing the sections cups release and I have to stick it to the side of the tank again. However my tank is round and I'm unsure if this is playing into the issue. Instead of having to worry about it coming free and floating to the top of the water I was able to add a small binder clip to the top of the cord which keeps it down in the water if it releases. Again I am unsure if it is due to my tank being round and not flat. Overall this is a great little heater for a small tank!

I've got 3 heaters I've tried and this one is my favorite. It is small and not in the way, even in the 5 gallon I have. My betta (Mario) actually loves to be near it and it doesn't cook his very long flowy fins. I love that I can set the temperature outside of the tank and then be able to look over at any point of the room and easily see the digital number very clearly. Some people might want one more "hidden" read out, but it makes me feel more secure that the thermometer is doing its job. It may actually suction too well. Once a month or as needed, I try to take it out for cleaning. I always have to battle the bottom suction cup. But again, I feel good that it's so secure and won't move and squish Mario or my snail (Tony). I have it set at 79 and have noticed it goes between 78 and 81 frequently throughout the day. But that doesn't seem to bother Mario or Tony so I don't mind either. I've had this for 3-4 months now and will update if anything should go wrong but I'm thinking of getting another one for my 15 gallon with my other Betta (Angelo) and several snails. That heater will not be named but its supposed to be stronger and its just not working out.

This product works well. It’s small and heated the water quickly and keeps the temp. I am using the heater for a turtle habitat.

I was a little nervous about this given some of the reviews, but pretty much every aquatic heater on Amazon has a decent amount of 1 star reviews. I'm using this in a 3 gallon tank I use for raising guppy fry until they are large enough to move to the larger aquariums I have for them. This has been amazing! I haven't modified it at all and used it for about a month now and I'm happy to report that every guppy survived. This heater does sometimes vary by 1 degree when the temperature drops below what it is set at but it quickly heats up again to the set temperature and it is never more than 1 degree lower which was not an issue for the babies. Honestly I prefer this to it always keeping the temp higher than what I set it at like some other models do since it pretty much guarantees that it will not cook your fish. None of my fish attempted to go behind the heater, so if I had a Betta I might place some netting around the suction cups on the back as one other reviewer did since Bettas do enjoy resting and hiding. Alternatively, I'd suggest giving your Betta more preferable resting places and hiding spots/keep the tank warm enough so he won't want to go behind the heater.

I love these heaters for my betta tanks, just be careful and make sure you have the right size tank, don't use these for a 1 gallon tank, which is honestly sad to do anyway but I digress. These are usually very reliable and accurate and after buying one to replace one that finally died after having it a long time (I want to say 2 years I believe?) the one I received was defective. It made a horrible sound and was either too hot or too cold. This is my first ever issue with these heaters and nothing can be perfect all the time. And they proved to have great customer service and responded to my message and sent me a replacement. I would recommend these heaters. I always suggest doing your own research but would definitely buy again and recommend to others.

This review is for the 50w heater. TLDR: dead/stopped working after 5 months Sept 17, 2020, was the day I purchased the 50-watt heater. I liked it so much, I bought a second 100-watt heater for my other tank. Well, the 50w heater died around the end of Feb 2021. So about 5 months. I cleaned it a couple of times when it started to look nasty. When I did my water changes, I made sure to unplug it as I also cleaned my filter at the same time. I noticed around the middle to end of Feb that my secondary temp gauge placed on the opposite side of the tank's heater started getting lower and lower than my preset temp of 84. I tried unplugging it to reset it, to no avail. I increased the temp at night to find out the temp reverts back to its default temp of 60 something. By the time I replaced the heater, my tank's temp was reading 65*. The 2 butterfly koi fish along with a couple of neon tetras have fought ick before and prevailed, I was worried I'd have to deal with ick again due to this heater going bad, but I think I got lucky as they look fine now. Prior to me noticing the heater failing, I noticed the koi's weren't moving around so much as these were quite active, almost always staying stationary at the bottom. They're in a 20g long tank with 7 mostly healthy java ferns. The heater started off in a 10g tank trying to raise/breed ghost shrimp, then I moved it to a 20g long after rearranging all my tanks. Going back to the pump, it never looked like it leaked, or made noises, or showed any other signs of going bad. So when I got paid, I went to Petco and purchased the Aqueon Pro 50. The heater was great while it lasted, which probably explains why it's so cheap compared to the LFS. Now I'm just waiting to see if my other one dies. I'll try to remember to update if it does go. Pros: -cheap -works well for the couple-several months you have it (also a con?) -decent length of cord -the 50w was able to maintain a good temp in a 20g tank after I moved it from a 10g Cons: -will die in the next couple-several months -not worth it to only last for a short period of time -would prefer the location of the button to be closer to the heater rather than the outlet as the tank setup sits in front of the outlet. PITA Remember, quality of quantity.

I recently purchased the FREESEA Aquarium Fish Tank Heater, and it has been a fantastic addition to my aquarium setup! This 50W submersible heater is specifically designed for small tanks, and it’s perfect for maintaining the right temperature for my betta fish and other aquatic friends. One of the standout features of this heater is its adjustable temperature external controller. Setting the desired temperature is a breeze, and the clear display allows me to monitor it at a glance. I’ve noticed that my fish are much more active and healthy since I started using this heater, which I attribute to the consistent temperature it maintains. The design of the heater is compact and sleek, making it easy to fit into my 1-10 gallon tank without taking up too much space. It’s also submersible, which means I can place it exactly where it’s needed for optimal heating. The installation process was straightforward, and I appreciated the included suction cups that keep the heater securely in place. I was also impressed by how quickly the heater warms up the water. It doesn’t take long to reach the desired temperature, and I feel confident that my fish are comfortable and safe. The heater has built-in safety features, such as over-temperature protection, which provides additional peace of mind. What I love most is its versatility; this heater is suitable for both freshwater and saltwater tanks, making it a great option if I decide to diversify my aquarium in the future. The quality of the materials used feels solid, and I expect it to last a long time. Overall, the FREESEA Aquarium Fish Tank Heater is an excellent choice for anyone with a small aquarium. It offers reliable heating, easy temperature control, and peace of mind for fish owners. I highly recommend this heater for keeping your aquatic pets happy and healthy!

There’s nothing I can really say good about this heater. However here’s a list of things that definitely need to be fixed - 1. It doesn’t keep a constant temperature. I have it set to 24°C and it fluctuates between 23°C and 26°C, which is stressing my fish. 2. The cord is not very long, only about 4 ft, luckily my aquarium is so close to an outlet, but I can only use it in this 1 aquarium, otherwise I’d need an extension cord. 3. The red light that shows the setting of the temperature is extremely bright. During the day it’s fine, but at night it illuminates the entire tank red. Luckily it’s only a 3 gal tank so it’s not extremely bothersome to me, but I’m sure the fish doesnt enjoy a brightly lit red tank at night. 4. I have it in my betta’s tank and he often swims behind the heater, most of the time it’s not a big deal, but I have noticed a couple times where he’s gotten stuck in between he plastic covering of the heater. I made sure he got himself out, and so far he hasn’t needed help, but he has definitely struggled with getting stuck, and although he hasn’t seemed to be injured from the heater, I’m worried about it burning him after reading some other reviews. I’m most likely going to buy a new heater, just for my fish’s safety. And I would suggest anyone else avoid buying this heater as well. Unless you’re fine with a glaring red light, temperature fluctuation, and your fish aren’t small enough to get stuck behind it.