Okay so I've been dealing with the same problem for quite some time now . I have a finished and insulated room in my basement with 22 tanks 10-220 gallons. The basement sits at right around 64 degrees and my tanks about the same . I went through completely re did all the insulation and bought a very expensive and good quality space heater to heat the room.. The thermostat reads 67 and will not kick off the room is way over but the cool air it picks up from the floor is not . It has not shut off at all in 3 days so my next thought a buying in thank heaters I will set them to 70-72 and higher if I am breeding this seems to be my only option right now let me know what you think . And this is the second space heater I've tried they all are doing nothing