





The most technologically advanced aquarium heater available today, Fluval E300 Advanced Electronic Heater with VueTech technology delivers peace of mind thanks to several excellent features.Equipped with an intelligent digital microprocessor monitoring system with dual temperature sensors, this heater continuously monitors and displays aquarium water temperature, ensuring the safety and well-being of your aquarium inhabitants.
Continuously monitors and displays aquarium water temperature in real time
Intelligent digital microprocessor monitoring system with dual temperature sensors
Ensures the safety and well-being of your aquarium inhabitants
Precision temperature control allows settings in 0.5-degree increments
Integrated fish guard provides advanced protection
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Russell D. Carroll –
Easily the best heater I’ve used in my 40+ years in the hobby
I spent a LOT of time figuring out which heaters to get to replace my eheim jager heaters that I’d used for 20+ years.In reading all the reviews of every heater and trying a bunch of different ones, the E series from Fluval was far and away the winner.I have been in the hobby 40+ years and have had that dreaded moment when you come home to a tank of dead fish b/c the heater malfunctioned. NO ONE in reviews for this heater had talked about that when I started shopping, and with the 8 I now I have, I can report the same – NO PROBLEMS – my tanks stay where they are supposed to!I’ve also had glass on heaters break – becoming a live wire in the fish tank. With these heaters – again, NO PROBLEMS – and the reviews support it. This heater is strong, and built to be nearly indestructible.I’ve also had, and always had, heaters that became difficult to adjust over time. That would slowly heat to a lower or higher temperature, and that became very difficult to adjust. This has led to disease outbreaks due to temperature fluctuations. With this heater – I’ve again had NO PROBLEMS!Most of the complaints I saw about this heater were due to seeing LF – Low Flow blinking. I figured, if that was the biggest problem I’d have, then this heater was a HUGE WIN, and it has been.Not to say I haven’t seen the dreaded LF indicator, but, I would state that I’ve always been able to address it. I run canister filters on all of my fish tanks and on all 8 of them, changing how the water flows out of the canister filter in the tank has resolved the issue. Sometimes it takes some fiddling – I’ll give you that, but all 8 of mine work perfectly and when I see LF – I know something has changed in the tank and is causing issues (for me – typically it is related to large plants blocking flow).I LOVE the always on display, like love, love, love it!At a glance I can tell if there are problems in temperature.I also appreciate how easy it is to adjust temperature, just flick the switch left or right and you are good. Easy Peasy.In the end – I started with one, and slowly, over 4 years, have replaced 8 or my 10 heaters with these, and I couldn’t be happier. They are easily the best heater I’ve had in my many years keeping fish.That said – I do have 2 complaints.1 – Replacing the rubber suction cups is currently very difficult b/c Fluval doesn’t make replacements very available.2 – It is very difficult to clean the heater housing if (when!) it becomes covered with hair or brown brush algae.Neither of those things are deal breakers for me, but are worth mentioning.
Josie –
amazing heater!
i bought this for my 55 gallon red eared slider tank, and it works great. it’s easy to set up and move around, the suction cups allow you to adjust how far in the water it goes. it’s not too big and fits in my tank well. it keeps my turtles water a comfortable temperature, even when the rest of the room is cold. i love that it comes with protective plastic casing, so i don’t have to worry about my destructive turtle trying to eat it!
Jay Galindo –
Great heater packed with features
This heater is great, I love how it has a digital temperature sensor so you can easily see the temperature of the water and how easy it is to adjust the temperature as well. Installation is straightforward like a heaters but this model does have an adjustable mount that lets you adjust it up and down and it also comes with an angle mount so you can place the heater in the corner of the tank. I had to purchase two because of the size of my tank so I wouldn’t have any cold spots but over all great item and very happy with my purchase.
M. Miller –
Works well. Takes fine tuning.
Firstly, I like the look of this unit. Also, the digital readout is neat. The adjustments are incredibly easy. Once positioned correctly, it holds temp well. That being said, it is finicky with placement. I initially had it in the center of my tank, vertically, with the red knob protruding, exactly like the directions say. All was well, until my first water change. After that I kept getting the error that it needed more circulation. You can unplug it and it will reset, but it continued to eventually error. So, I moved one of my large airstone directly underneath, and it has worked flawlessly ever since. So make sure it is placed where there is plenty of movement.I have read that others have had luck with placing it fully submerged horizontally. But I chose to stick with what the directions say. Plus horizontally would mean the digital readout would be sideways.I have the 300 watt in a 55 gallon. I have the temp set at 78.5°. My accurate thermometer reads between 78.5° and 78.9° at all times. Not too bad. My Eheim was a bit more stable, but really sucked to try to change the temp as the dial was awful. Plus after 2 years I started to notice some moisture in the glass, which is what led me to this purchase.
Matt –
Works great with a few tips.
I generally don’t leave reviews for products, even ones I love, but I wanted to clear up an issue people were having with this heater in comparison to others.The temperature indication is spot on, very accurate. The design is sleek and well constructed. The issue I was having with this unit was not being able to maintain tank temperature in a very cold room, even though I oversized the wattage/gallons ratio by over double the recommended specifications. I believe the shrouding around the glass mildly hinders heat distribution so it is important that this unit gets adequate flow from the filter.I placed the heater directly under my filter return but still randomly had scenarios where the temperature dropped and stayed in the blue, even for a couple days. Then it would rise to green and maintain no problem. What I realized over time was whenever I did water changes or added water, the temperature dropped that night, even if the water added was warmer than the tank water. As the water level dropped over the next few days from evaporation, the temperature rose back up to normal.My hypothesis: If the water level in the tank is a hair too high, there is less disturbance created from the filter return, even though you are still achieving the same turnover rate. Try either lowering the water level in half inch increments until the temperature is able to maintain, or try rotating the heater sideways to achieve more flow through the shrouding. I recommend the first option because turning the heater sideways looks ridiculous with the digital display.I now maintain 77-78 degrees constantly in a 55 degree room and would purchase this heater again. Fluval makes excellent products.
atlansar –
Chauffe correctement et peu se regler facilement
Khushwinder Mann –
I received this product in a damaged and used condition, which was disappointing. The item clearly showed signs of white minral deposit on black plastic, and the packaging was in poor shape. I expected a new and undamaged product, so this was a letdown. I would advise caution when purchasing from this seller to avoid a similar experience.
cindy –
shipping tres rapide et je l’ai eu a tres bon prix et fonctionne a la merveille. chauffe eau de qualité tres important par contre de suivre les instructions, il lui faut quelque minute avant detre conecté pour saclimater a la temperature de l’eau avant de le connecter sinon il fonctionne pas, apres il est tres simple a utiliser et indique la temperature avec précision.
David –
I was having problems keeping my new tropical aquarium temperature stable, even though I was using the correct sized heater for my tank. So I did some research into my fluctuating heat problem. I found on the internet that my problem might be caused, by my house being too cold, due to me living in the countryside. It recommended that I used the next sized heater up from mine or to use 2 heaters to stabilize the temperature. Being that my heater I had was a 200 wat I decided to go for a 300 watt heater. My next problem was, which make to go for.. For this again I turned to the internet, on the reviews done on the different makes.I was guided towards the “Fluval E300” by being one of the top recommended by the review web sites. From there I went on the Amazon web site. I checked the customer reviews. They were very mixed, in their opinions. So I was unsure but noticed there was a couple of reviews that stated that if you followed what they had done, all was well & that would rectify those problems the other reviewers were having, while using this item. So it was at this point I ordered it, even though it was quite expensive compared to some others at Amazon.It arrived the next day via Amazon Prime Delivery. I eagerly unpacked it and swapped it over. I followed what some of the other reviewers had stated to do, just so I could get the best out of this heater.1st; I placed it at a 45° angle in the aquarium, as per the other reviewers advice.2nd; I made sure it had a good water flow over it3rd; adjusted the temperature to what I required. Then left it alone to hopefully sort out my heating issues.The next day I went straight to the aquarium, to check the temperature of it, against my other thermostat placed on the opposite side of the aquarium to the heater, I was very skeptical at this point. Well low & behold it was within 0.4°c difference. Since having this “Fluval E300” heater I have checked the temperature on numerous occasions and the temperature hasn’t changed, even during the night, when it is at it’s lowest room temperature. I would definitely recommend these “Fluval E series” heaters but just be guided by the above advice and other helpful reviews please, and it will be a great product for you, just as it is for me5++ highly recommended itemtime has moved on now and at least 6month & still the heater is perfect keeping good temperature
Hasan –
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