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Hydor Submersible Glass Aquarium Heater - Original Theo
|Price:||$15.29 & FREE Shipping on orders over $49. Details|
|You Save:||$5.70 (27%)|
- High resistance - the first shatter proof heater
- Shock resistant
- Position vertical, horizontal and completely submerged
- Graduated scale for precise maintenance of set temperature
- No damage in case of running dry
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Size: 25 Watt
Top Customer Reviews
This heater, on the other hand, while larger and more obtrusive, does a much better job in regulating water temperature. I never have to worry about finding my tank temps in the high 80s the way I did with the other heater. Also, the fact that it has a regulator dial is a huge plus. While the dial calibration may be off by a degree or two, it does work. You turn it up, the water temp goes up (but not too high). Also, the little indicator light is a nice way of checking that the heater is on and working.
Even for small tanks, I would skip the unregulated 7.5W and 10W heaters and go with this one.
Also, it's worth mentioning that the heater doesn't look exactly like the one in the main picture. It's shorter and fatter (proportionately at least...) than pictured. This isn't a bad thing. Just don't freak out, because you ARE getting what you ordered.
Small tanks, typically used for Bettas, always have the issue of heating them and due to their small size most heaters will not fit. Well, this small 25W heater works perfectly in my 5.5 gallon aquarium easily fitting vertically with plenty of space to spare above and below. The thermostat on top is labeled in temperature, versus just a + and - or arbitrary scale (like 1 to 10). The temperature may not match the dial right out of the box, but really that's not a big deal. If you need it a degree warmer, you turn the dial up 1 degree. This is assuming you are not exceeding the capabilities of the heater, which I explain in more detail below.
I'd like to point out that this is a very low wattage heater. So while it works fine on my 5.5g aquarium you should know that it will only do fine if your room temperature is somewhat close to your desired tank temperature. If you keep your tank at 78 degrees, but in the winter your house is at 65 degrees this heater will not be able to make up the 13 degree difference. Small tanks loose heat fast, and this heater at just 25W will not be able to keep up with that.
Because of this some people will mistakenly say "It can't heat my tank even when I turn it up to high". As I mentioned earlier, these have a thermostat so they work only on temperature. If it is set for 78 and the tank is only getting up to 76, it is doing its best to heat the tank to the set 78. Turning it up to 85 degrees does not change that. The heater will not turn on, and stay on 24/7 and the reason is so that it doesn't super heat itself.
How low your house can be for this to work will depend greatly on your specific tank dimensions, what's in it, and your filter flow.Read more ›
I bought this product because I was going into an apartment with roommates who I knew wouldn't want to pay to keep the air temperature at Betta-friendly levels. So I spent months looking at the different options on Amazon and trying to make heads or tails of which tank heater I should get and being very indecisive. In the end I decided to give this heater a try for it's cost, adjustable heat setting, and the overall positive things I was reading in people's review.
Although the temperature on the heater control does not usually match the temperature on my tank's thermometer, this hasn't proven a problem at all as it just requires me to tweak the heater's control until the tank thermometer shows the water is at the temperature I want. Therefore the fact that heater and thermometer are at different temperatures is inconsequential. The heater is doing it's job and keeping my tank at Betta-friendly temperature
So this is a solid choice for consideration in your search for a tank heater.
The positives and negatives so far
Positives: submersible, temperature control, keeps tank at a constant temperature
Negative: if the air temperature outside the tank changes you may have to tweak the heater's temperature setting, temperature set on the heater may not match the temperature in the tank
Most Recent Customer Reviews
This was a good product at a very reasonable price. With very prompt arrival.Published 4 days ago by matthew s goins
Love this heater! My betta is in a temporary 2.5 gallon tank and I was nervous about choosing a proper heater for him in the meantime since typically mini aquarium heaters do not... Read morePublished 10 days ago by Amazon Customer
This is the best heater for small tanks, hands down. I have tried 4 different heaters for my small betta tanks, and this is the only one that works, and works great. Read morePublished 12 days ago by Karen Hall
Lots of research went in to me buying this for my Betta. Adjustable thermostat makes it easy to keep his 2.5 gallon tank at 78-80 degrees. Read morePublished 18 days ago by Amazon Customer
Last winter my heater died after a year of use, I got another heater that failed after a few months. (All from aquarium shop recommendations). Read morePublished 19 days ago by Mary
I used this heater prior to upgrading to my 10 gallon tank and it worked very well. I had been using it in my 5 gallon betta tank. Read morePublished 19 days ago by CosmicGhost
Keeping my water at correct temperature for my bedroom aquaponics setup. Sturdy well built.Published 22 days ago by Amazon Customer