All of the biocubes that I had were just fine out of the box. I even did a MH retro into a BC29, and it was totally fine on its own.
Whats your house thermostat set at?
Two things I would do:
1. Make a small gap inbetween your canopy and tank. This allows airflow onto the surface of the water
2. Upgrade your fans
To tell you the truth, I instantly upgraded the fans when I bought my biocubes. I found them noisey anyways. Theres lots of threads on fan upgrades out there.
www.nano-reef.com has an excellent biocube resource section that you could look at as well.