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Hydor Theo Aquarium Heater

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Hydor Theo Aquarium Heater


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25W - Hydor Theo Heater
SKU: 202170
Earn 19 Reward Points
50W - Hydor Theo Heater
SKU: 202171
Earn 22 Reward Points
100W - Hydor Theo Heater
SKU: 202172
Earn 21 Reward Points

reg. $23.99

Special Price: $21.59

150W - Hydor Theo Heater
SKU: 202173
Earn 24 Reward Points
200W - Hydor Theo Heater
SKU: 202174
Earn 25 Reward Points
300W - Hydor Theo Heater
SKU: 202175
Earn 29 Reward Points
400W - Hydor Theo Heater
SKU: 202176
Earn 29 Reward Points

reg. $32.99

Special Price: $29.69

  • Dont waste your money By Chris on 1/19/2015

    I Bought 2 150w heaters and both are not accurate, turned all the way down one heater hit 85 while the other was over 90, I now only use these heaters to do my water changes, still need to unplug to let them cool down though.
  • it will cook your tank! By vtocean on 1/9/2015

    Bought the 300 watt version and even on the coldest setting stays on with the tank temp over 82 degrees. This has been wildly erratic and is less than 10 months old. Unless this is run on a controller, I wouldn't trust it at all. I had expected a better unit from hydor....needless to say, I use it for water changes only and sometimes need to unplug and wait for the water to cool. Worst part is that at times it seems to work as it should....extremely inaccurate at best and a tank cooker at worst.
  • Decent heater for the money By Chris on 12/11/2014

    I bought this heater for a small nano tank and not really impressed with it. It seems to fluctuate a lot even when the room temp is constant. I will upgrade to a better heater later
  • Horrible heater! By perry on 7/23/2014

    I have had 2 of these heaters break already and have had to call hydor both times and I am still waiting for my other one to arrive. I am planning on buying the Cobalt Aquatics Neo-Therm heater.
  • Broke after 6 months and killed all my fish By AngryBeaver on 2/17/2014

    Heater worked great for 6 months on a 55gal tank... then I started loosing fish.. I did a water change and noticed the temp was very high and the heater was still on.... Using a digital thermometer I found the water to be 86 degrees. Unfortunately, I was to late for most of the fish in the tank... I contacted Hydor for a replacement and they wanted me to send the unit in for them repair it. Sorry not worth my time or effort.. they got my $30 this time, but that will be the last $30 they ever get from me.
  • Would not turn off! By Steve on 1/20/2014

    This heater's gauge seems to have stopped working after only a week! It stays on even when I've dialed it up to the maximum and my water temperature is about 10 degrees below that.
  • Keeps temp stable but prone to leaking. By Tek on 12/13/2013

    I have had 2 of these forminternal condensation within the first month.
  • Good Value For 400W By Jeff on 6/1/2013

    I have the 400W version - it is the cheapest and most powerful among the heaters I use, but it also gives the biggest temperature swing (almost 2 degrees compared to 0.5 for the others).

    My guess is that the temperature sensitivity is not as responsive, so make sure it is fully submerged in a spot with good water flow.

    For this item, I would not recommend buying a model that is rated for a larger aquarium size than what you have.
  • Works as its supposed to By TROJAN on 5/7/2013

    I have a 50w just for my Q.Tank and have not had any issues with this brand and model so thats what im sticking with till it fails to meet the use.
  • Do not purchase! By Anthony on 5/4/2013

    I have had these in the past and they did not perform well. Just recently purchased a 300W unit and after a week, it is sticking on. I like to keep my reef tank warm, but even if I drop the temp towards 70 degrees, the heater kicks on and tries to raise it around 85. I'm running LED's with a Vortech, so not much heat from equipment. House temp is 70 degrees as well.

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