Jetsu Submersible Aquarium Heater - Glass 100-Watt, for Freshwater Aquarium and Saltwater Aquarium, 12 Month Guarantee, New Range of Aquarium Supplies

Seems to work as desired. Just ordered a second one for my aquarium. I've now updated this review because my second heater came (as a backup) and now the first one I ordered just shattered in the tank. Can't think how that happened but the bottom blew out of it so there is glass all over my rocks that I have to fish out. I can't remember bumping it or anything but just a heads up that they are pretty fragile so take care when installing or changing the temp.On another note, these are fully submersible so with that said if you choose to utilize them in that way it gets tricky to change the temp up or down because the knob is pretty hard to change and nearly impossible under water hanging off the back of your tank so you have to turn it off, let it cool for 15 minutes and then remove it from the water before adjusting the temp...kind of a pain but if you can get the temp dialed in you should be good to go. I'm now ordering my third one in three weeks. LOL

This heater is slightly confusing with the temp in Celsius, but I figured for the price I would give it a try. It worked great for about 18 months. I know I should have replaced it at that time, since it was in a saltwater tank and that is about the heater lifespan. I didn't. It ended up cooking a good amount of my coral. When this heater broke, it remained on and HOT. The temperature got up to 88.8 degrees. So while it worked, when it failed, instead of being good and just not heating, it drastically overheated everything. Side note, I've had better luck with livestock and corals living through a cold wave when a heater dies vs a heat wave.

Came with directions and a temp. Chart. it recommends you have 2 heaters in your aquarium at all times. I've never heard that before and I have 2 seprerste fish tanks. After setting them both up only 1 works. So it made me wonder if they sale 2 then maybe That's because they expect one to have problems or not work. Then one that works does a decent job though

I bought this heater for my aquatic turtle tank. It has a wide scale of temperature settings which allows me to maintain the water temperature at about 82 degrees which seems to be perfect. The glass is easy to clean & the suction cups are holding it firmly in place. It is a good product for the price. The temperature dial is in Celsius, but it comes with a conversion chart to Fahrenheit, which is easy to understand.

Works perfectly and clicks on when it needs to. I have a separate thermometer and tested it to make sure it runs when the temperature drops below the level I set. (-1 star) because the "thermostat" is in metric units.

Our turtle, Speedy, is nice and warm. This has done just what it said it would do. Ordered this back in October (or November) and we haven't had any problems with the heater.

Our fishes are loving their new heater. It came in the nick of time. I normally keep my thermostat at 65°. This past week the temperatures have been in the upper 40°s to the lower to mid 50°s, resulting in my house being well below 65° in the mornings. I have not had to worry a bit about my fish, as they are happily swimming in their 70° tank. Thank you so much for your product!!

Instructions leave a little to be desired and it is a pain to have to adjust it over the first week to dial in the temperature but overall a great value