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Hydor Submersible Aquarium Heater by Hydor

  • $77.99
  • Save $39SALE (50%)
In Stock - FREE shipping over $75
SKU: HY00320
UPC: 841421003207
MPN: T11502

Hydor Submersible Aquarium Heater Description

The Hydor Aquarium Heater is a submersible heater made with the exclusive PTC (Positive Thermal Coefficient) technology. This Hydor aquarium heater provides no thermal shock, is submersible, and engineered shatterproof glass designed to resist breakage in most normal aquarium situations.

  • Ideal for Freshwater or Saltwater Aquariums
  • Heater can be positioned vertical or horizontal
  • The Hydor heater cord is approximately 6 feet long

The Hydor Aquarium Heater has all the necessary features for safe and precise temperature maintenance of water in your tank. The exclusive technology and the high quality of the components guarantee a long lasting product.

25 Watt: 2-7 Gallons (6.9" Long)
300 Watt: 53-80 Gallons (15.5" Long)
400 Watt: 80-105 Gallons (15.5" Long)

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Hydor Submersible Aquarium Heater Customer Reviews

Mac, Elon NC on 2014/01/04
Great heater would recommend

Bought the 50W for my Fluval Edge 6 gallon. Heater works great and I like the fact a little orange light comes on to let you know when it's heating. Keeps steady temps and is accurate to 1 degree of my two thermometers. Will buy another when I figure out what I'm going to do with the Fluval 12 gallon I recently picked up for cheap.

Tyrone, Paramus NJ on 2013/12/17
Great product my fish loved

I got my order very fast. I started using the heater and it works great, I love it.

Barbara, Charlottesville VA on 2013/07/20
My SIXTH one!

I've already written a review, but since I was asked to write another one, here goes. I bought the 25 w for my grandson's Betta tank, as I find it's the best heater on the internet, both in quality and price, and you get the added bonus of having a submersible heater! I might add, if your tank gets any amount of sunshine during the day, keep an eye on the temperature control and adjust accordingly - you may have to lower the temperature setting to compensate for the warm air in your house and the sunshine helping to heat your tank water. Great product, no matter how you slice it!

Kendra, Fort Worth MN on 2013/07/07

I bought the 50 Watt for my 10 gallon betta tank (because it's the same price as the 25 Watt) and it works great! It has a wide temp range and easily went up to 85 degrees while treating ich. I even bought a second one for my 5.5 gallon and plan on buying another one for my future 10g. Great price as well!

Barbara, Charlottesville VA on 2013/06/26
A MUST HAVE for Betta Tanks

This heater is a must have for anyone who keeps Bettas in small aquariums, or anyone who uses a 5 gallon tank. It is the best submersible heater I have found and the price is the most reasonable on the internet. I have 5 of them for my 4 Betta tanks and my 5 gallon fry "grow-out" tank.

Jessica, Texarkana AR on 2013/04/27
This is the third time Im buying this!

As the title says, it's my third one! I'm so in love with these heaters... The first one, I have now had for about two years! It is the smaller 25w one, but the fact that it has lasted this long (and will probably keep lasting me for a good while) says a LOT! Most smaller heaters are poor quality, defective, and while cheap they only last a few months... and as a fellow betta keeper, I have come across MANY other betta owners that have bought cheap heaters for the convenience of price and it didn't last them even three months. The second heater, I actually bought for a friend of mine who also has a betta- poor thing never had a heater until I got one for it and that betta enjoyed the warm tropical temperature as much as mine does. I'm only buying my third heater because I recently got another fish tank for a new betta... and I know the hydor theo is too reliable and too great of a bargain to pass it up. Heating aside, it also feels durable. I was originally worried I might break it because it's made out of glass or something that feels a lot like it... but once you get past that feeling, you find that it is indeed a durable little thing. I've accidentally banged it here and there and it still works like a charm. The light is very convenient to know the heater is still working. It's very easy to clean if debree like bits of algae or dirt from your substrate gets onto it, and the fact that it's submersible and has FANTASTIC suction cups means it's very easy to move around and position in your tank. As I said, it's been about 2 years and the suction cups are still working great (and that's saying something for suction cups!) All and all I can't help but recommend this to anybody looking into a heater... I know there are some people that have experienced defective heaters, but I'd honestly have to say it's the luck of the draw from the manufacturer. Definitely dig into reviews and see how many actually deal with defectiveness involving a great quality heater such as this.

Glitched, Independence MO on 2012/12/31
Great for Nano tanks

I have had this in a Aqueon 2.5g Mini Bowfront for almost a year now and it works great. I have to set the temp lower than what it states on the dial, but that is to be expected due to the small size of the tank. Once I fiddled with the temp setting a bit it holds my Betta tank at a steady 78 deg, which is perfect. I would totally recommend it to anyone with less than a 5 gal tank as long as they knew to work with it a bit to get the temp correct before they state that it is to hot.

Chris, West Covina CA on 2012/03/11
Heater malfunction

Ordered two heaters. One of them works great. The other malfunctioned. Indicator light stays on but does not heat...

Ying, San Jose CA on 2011/05/27
Compact, good-looking heater

Compact enough to fit in corner of my 10g tank to not look cluttered. Nice glassy look and easy to adjust temperature dial. Works great, looks clean, easy to set-up and it generously comes with two suction cups.

Tna, York ME on 2011/04/24
Efficient..good price!

The heater works real well and adjusts good. Submersible feature is very useful since our tank has a cover.

Ying, Los Gatos CA on 2011/04/09
Great heater, buying another!

I purchased the 300 Watt one for my 55g tank - nice looking heater, stays very neat with the suction cup attachment, easy to adjust temperature, sturdy enough to withstand curious bumps and mouthing from my active large goldfish, and best of all, IT WORKS! Keeps the water nice and warm and my fish happy even though the tank is in the coldest room of my house!

Rob Lee , Alameda CA on 2011/03/12
works great,no problems

Aquarium heater and thermometer with alert were better than expected and will use Pet mountain again.

Erin, West Jordan UT on 2010/12/14
Works great so far

We purchased this heater for a 12 gallon aquarium and so far it seems to be working. The orange light comes on when the heater is on. I dont have a separate thermometer to test the actual temperature, but I have confidence that its working. The heater was easy to install and its easy to see the different temperature settings.

Sherry, Vinita OK on 2010/11/30
Does the job!

Id been having problems maintaining an even temp in my fish tank and tried this heater. It does a fine job - stays within 1 degree +/- without fail. Im very happy with it.

Dusty, Erwin TN on 2010/09/07

My wife got the 200 watt hydro theo from a friend. Is still very accurate being used for months. would definitely recommend.

Jessi, Franklin WI on 2010/06/27
buying a second!

No problems.

M, Monrovia CA on 2010/06/09
So far so good!

I have only had this heater a few weeks so far, but it seems to be working quite well! It has kept the temperature regulated since I put it in, and does not feel too hot to the touch, which I like because my turtles like to touch it! It also seems to stay in place well. Overall, I like it so far!

Courtney, Marysville WA on 2010/02/19
Four years and still going strong.

I bought this heater for my 10 gallon approximately four and a half years ago. To this day, the temperature only fluctuates by 1 degree, which seems fairly small and it only fluctuates when I turn the light on and off. Great product. Looking to buy one for a 5 gallon tank for my dwarf puffer.

Van, Des Moines IA on 2008/02/21
Very good heat Ive ever seen

I boght this head for my tank 75G, it keeps exactly the temp as I swith to. I recommend this heater for big tank

Care, Manchester NH on 2007/11/03

Great heater and VERY precise! Can't beat these prices here =)

Amanda, Philadelphia PA on 2007/06/30
Fish Friendly

I am able to use this heater with my seahorses and not worry about them getting burnt. I would definitely recommend this product to anyone with curious fish!

Drew, Fresno CA on 2006/11/14

It is better than expected for a very decent price. Also, works like a charm!