Review on 🐠 Fluval E300 Electronic Heater - 300W Advanced Aquarium Heater for Tanks up to 100 Gallons (A774) by Paula Jones

Great heater and very accurate. It's within 0.5 degrees of my thermometer. There are a few steps that need to be followed to get it working properly. I would like Fluval to update their manual as the vertical mounting of this heater according to their instructions is incorrect. Your support will provide you with updated instructions on how to set it up correctly when you contact them. Here's what I did to make it work properly: 1- It MUST be mounted at a 45 degree angle with the bottom end facing the filter inlet. If you can also direct the outlet of your filter to push water there, that's even better. Look at my photo and you will see how mine is and absolutely NO "low flow" messages. 2- Leave it in your tank for about 20 minutes, then turn it on and wait about a minute before setting any temperatures. (It will do a self test and turn some heat on and off to calibrate). 3- Don't expect it to heat up your tank right away. This is a very gentle heater. It took about 2 days to finally get my 65 gallon tank up to temperature (it wasn't too bad since I had filled it with water that was 2 or 3 degrees off the desired temperature, which is what Fluval does in recommends in his manual). Make sure your water is about the temperature you want it to be. Once it reaches the desired temperature, it turns green and the temperature stays the same, no deviation, unlike other heaters (provided you followed N#1). As for me, if you get it working properly it will be the best and most accurate heater I've ever had (I've had Eheims, Marineland, etc.). Because it is a smart and very VISUAL heater, it will let you know everything that is going on. So don't be surprised if it stays blue or red for a long time, small changes in temperature and it will let you know. Don't let that bother you, we're used to 'dumb' heaters that only have an on/off indicator, you think they're working but they don't tell you if your water has dropped 2 degrees or similar. I hope the above helps and have again deducted a star just because Fluval is to blame for not having printed a better guide explaining the above and waiting for customers to contact/complain to finally to submit an email explaining these things.