GOOBAT Fish Tank Titanium Heater 100W, Submersible Aquarium Heating with Intelligent LED Temperature Display and Thermometer

100w - it's a good heater. It's has current temp display meaning one less thing in the tank, easy to set up and easy to check whether it's currently heating or not via the LED.The temperature read out is bright, but not bright enough it'll illuminate the tank. Bright in the sense you'd spot it in a dark room without tank lights on.Temperature control is great through the out of water controller, just press it, get your temp. Job done.Only fill units of temperature, so no half degrees.It holds temperature perfectly. Significantly better than my tetra heater that varies by as much as 1c before it'll kick in. This thing seems to hold steady within 0.3c in my tank.The only complaint is the massive under measurement of temperature. It shows a solid 3c cooler than it actually is as checked against 3 other thermometers. This isn't an issue in my book as it can be managed and carefully checked, and as long as temperatures are stable I'm not concerned about swings. Just sit your tank 2-3c lower than you would normally.Construction is great, feels quality.

After reading mixed reviews of this heater, i decided to take a chance and attributed the negative ones down to having not been installed correctly. Having installed the heater completely submerged in my tank, at an angle, the heater worked great. For about an hour. Then it promptly stopped and the LED display started flashing. No error codes, just flashing and the temperature of the water rapidly dropped.After unplugging and plugging in again, it again worked fine for about 15 minutes before the LED began constantly flashing again. This time i left it in place overnight to see if anything happened. Nope. Woke up the next day to it still flashing and cold water. Fortunately my tank was in the process of being set up and had no fish in, otherwise i dread to think how many would have survived. Returned for a refund and an Interpet Deltatherm heater purchased instead which works great

Nice sleek design and good screen, had a problem with my first one, notified seller and shipped me a new one straight away, I have 2 other heaters the same brand and they work fantastic, excellent customer service as well

Unlike many aquarium heaters this unit MUST be totally immersed. Initially I did do that, mounting it vertically as most users will do, but couldn't get it to stop giving me an E1 error. It was only when I took it off its clips and tested it in a horizontal position that a tiny bubble of air came out of the top and it started to work normally. Clearly trapped air has the same effect as incomplete immersion!It can display the temperature in Fahrenheit or Celsius. Both that and the temperature limit are set by an external button. The hard bit is to read the temperature when it is below eye level in turbulent water.These points may be considered 'niggles' but they do detract from an otherwise excellent product. The instructions are 'foreign English' in nature but comprehensible.

Perfect thermometer, so handy being able to clearly see the temperature clearly and accurately and love having the controls outside the tank if it needs adjusting.I had a slight issue at first that it came up with an error, all I did was unplug it and shake it underwater, this dislodged a few air bubbles and then it worked perfectly. I think an air bubble was over the sensor that stops it working if it's not submerged. This isn't a bad thing as if you're doing a water change and forget to turn it off it's very handy that it cuts out rather than overheats.

1 Yr update, it has broken and needs to be replaced. I hate heaters because it seems like no one sells a heater that will last a good amount of time if not forever. Very dissapointed to discover this is no longer working at all and has left my fish in cold water. Would not buy again.Old review/first impression --- i had the issue of it showing the error like many other reviewers. I tried many positions but eventually got frustrated and left it in the tank. After a couple of hours the error message was gone and it was heating the tank and doing its job and I have not had any problems since. I think the error could've been caused by me turning on the heater whilst it was not fully submerged (I think at the time whilst I was testing positions I turned it on whilst the very top of it was out of water. This is one of the explained reasons of the E1 error on the instruction sheet you get with the heater, so I think that is what happened for me).I really like that it shows the temperature on the heater and that you can control the temp with a button from outside. This makes changing and adjusting temp really easy.

As mentioned in previous reviews the unit wont work unless you get ALL of the air out of the until before switching on. Solid construction, easy to set up and I like the digital temperature reading which is very clear but doesn't dominate the tank.

The concept of this heater is brilliant. The light wasn’t too bright and it was very easy and simple to use. However, just over a month after putting it in my tank this weird almost transparent liquid started leaking from the bottom.I’ve put a waterproof light at the bottom of my tank and that’s how I noticed it. I’ve turned the heater on and off just to be sure it was definitely coming from the heater, and it was. My fish got sick and eventually died.