Over Heating Tank

[Jennifer W]

Help! Last night I set up my Red Sea Max Nano 20g tank and I noticed after a short time of having it running that the heater was set to 78 and the tank temperature was 91!!! I immediately unplugged the heater and figured I’d leave it off overnight and it would naturally cool to the room temperature which was set to 72. When I woke up this morning the water is still like bath water! I don’t know what’s creating so much heat??? Does anyone have any suggestions?

[Jaren45]

Check all powerheads, return pumps, any moving part really. In that little of water, a faulty return pump that has debris or something in it can definitely be generating excess heat

[A.m.P]

In the meantime I'd drop some frozen water bottles or a ziplock with ice somewhere with decent flow to cool things

[Tired]

You should get an Inkbird controller for your heater. All heaters have a risk of failing on, which will cook your tank. If it's plugged into an Inkbird that's set to shut the heater off at 80 degrees, both the heater and the Inkbird have to fail for the tank to get overheated, which is vanishingly unlikely. 

 

Yeah, something in there is generating heat, other than the heater. Turn everything off except one device, and see if it cools down. If so, turn that device off, turn another thing on, and so on, until you find the culprit. 

[gen]

A controller is indeed a great fail safe, in the last 2 years, I had to change 3 times my heater (twice for overheating). 

 

Don't forget to top off water in the meanwhile, lot of heat usually means lot of evaporation. 

 

Checking your equipment one by one is indeed the way to go. Don't forget to check your lights (a led system going full power just over the water surface will generate a lot of heat) and the tank surroundings. 

[banasophia]

On 10/9/2021 at 5:59 AM, Jennifer W said:

Help! Last night I set up my Red Sea Max Nano 20g tank and I noticed after a short time of having it running that the heater was set to 78 and the tank temperature was 91!!! I immediately unplugged the heater and figured I’d leave it off overnight and it would naturally cool to the room temperature which was set to 72. When I woke up this morning the water is still like bath water! I don’t know what’s creating so much heat??? Does anyone have any suggestions?

Okay, I’m not sure why this might happen, but I seem to recall my tanks getting really warm the first day or two after I set them up then dropping to a normal temperature. 
 

I think your tank is brand new, did you have any livestock? What kind of rock? Did you add any beneficial bacteria products? Is your equipment all new? Is your thermometer accurate? 

[DaJMasta]

Pumps can generate extra heat when they are grimy, so cleaning them can be good, otherwise lighting will contribute some as well (less as LED, but still can be a bit), and something like a hood can keep it in instead of allowing venting the heat and normal evaporation.

 

Heaters are prone to failure, but the temperature dials on them are often several degrees off, so I'd start by turning down the setting quite a bit and seeing if it helps or if the heater is stuck on.  Worth mentioning that if your heater always being on can give you 20F over ambient, it may be slightly oversized for the tank size.  I am a fan of using lower recommendations for wattage (since pumps and lights all contribute) and splitting it across two heaters.  That way if one does get stuck on, the maximum temperature it can push it to is not as high as if it were just a single unit.

So long as you don't have any livestock yet, you've got time to figure out whatever the issue is, just keep in mind that a large volume of water will take hours to reflect a significant change in temperature, so let it settle for a bit after making an adjustment.