Eheim Jager tru temp can't keep up.

[rvlcf]

I set up a reefer 450, 116 gallons, and purchased a new Eheim tru temp heater
250 watt. The heater is rated to work between 106 and 159 gallons. It can't get the temp over 70 degrees. I added a secondary small heater to get the temp to 80 degrees and when it reached 80 I unplugged it, hoping the Eheim would maintain it at 80. The temp fell back to 70 overnight. It has been on the whole time, with the orange light on.
Does anyone think i have a defective heater, or is the rating on this heater incorrect?
Thanks for your input.

 

[HiddenUser]

I can't say I have experience with Ehiems, but I always run multiple heaters in the event of one failing. I have used Cobalt Neotherms and some Finnex Titanium Heaters and it seems like they're all rated incorrectly?

Maybe your ambient air temp is low enough to where your heater is having a hard time keeping up?

 

[rvlcf]

Between here and Reefcentral i've received varying answers.
Called Marine Depot and they are sending a replacement. We'll see if it was defective,
or just doesn't have the chops to keep up!
Will run 2 heaters as a safety measure.
Thank you for your response, much appreciated.

 

[dbrewsky]

yeah, heaters cannot really be rated by volume because ambient temperature surround the aquarium, drafts from vents or windows, and evaporation all come into consideration. My 120 should run on two heaters, however, being in our basement which doesn't receive direct heat, required me to add a third to ensure the coldest days did not bring the tank temperature down.