# heater question for 125 gallon



## jmk (Oct 30, 2004)

Ok in the process of setting up a 125 gallon, my house stays around 68. what wattage heater should I use and should I use 1 or 2?


----------



## Morpheus (Nov 12, 2008)

One heater, 250 watts. Just my opinion.


----------



## zcfish (Jan 31, 2009)

I'd go for 2 so if one goes bad it doesn't heat up or cool down that fast. Maybe two 150w. I have a 250w and another 50w it keeps 78F in the basement which is 60F. I do have insulation though on all four sides most of the time.


----------



## mel_cp6 (Feb 3, 2009)

i use a 300watts for mine for my 125gl.


----------



## mithesaint (Oct 31, 2006)

I'd go with two heaters. Your heater wattage needs depend on tank size, location of tank, filtration method, etc. No easy answer.

You're in MN? The thermostat on that interior wall might read 68, but I'd bet that the temp right up against an exterior wall would be significantly colder in January in MN. What are you using for filtration? A sump increases the gallonage and also contributes to heat loss. Do you have styrofoam under the tank? That helps too.

For some people (morpheus in FL), a single 250 is enough. For my 135 with a sump in my cool basement in Buffalo, I ended up needing 700 watts to maintain a stable 80 degrees. Yikes. In all reality, I could probably pull out the 200 watt heater and be ok, but 450 watts certainly wasn't enough.

Long story short, I'd get two 200 watt heaters and go from there.


----------



## fmueller (Jan 11, 2004)

Another point to consider is that not all 300W filters appear to be equal - even though theoretically at least they should be. I found that the Hydor external thermal heaters seems to do a better job than some other heaters of allegedly same wattage - apart from allowing for installation invisible in your tank. Unfortunately they are not cheap. I love the Hydor ETH 300 on 125G tropheus setup.









_Hydor ETH 300_


----------



## boredatwork (Sep 14, 2007)

I use the Hydor 300W for my 125, and I have had a lot more success with it then when I used 2 x 250W Visitherms.


----------



## Jowlz (Dec 19, 2008)

I'm the over kill guy. I went with 2 300w hydor eth. My house doesn't stay at a constant temperature. It's not unusual for the area of the house the tank is in to drop into the 50's.


----------



## SupeDM (Jan 26, 2009)

I live near the Twin Cities and In my 125 gallon tank I run 2 300 watt heaters. Last winter my furnace broke down and My Hosue temp went below zero inside. I had a 5 gallon tank sitting next to my 125 that froze solid but the heaters kept my 125 over 75 degrees for two days like this. I did tape blankets around the tank though.


----------

