take a look at my build thread on my BC 29

http://maast.org/forums/showthread.php?t=53905

There are several of us on here with them. Skimmer is not necessary nor is a heater. There are lots on here who run 100g plus tank without heaters. You must realize that your pumps, lights and other equipment create heat.

Have fun with it, ive had a lot of large aquariums from 100g-200gs but really enjoy the simplicity of my Bio Cube.