I also had a candy cane in a 14G BioCube. I started with it in the lower half of the tank and then moved it to be about 2/3 of the way up, probably about where you want to put it. It did fine in both locations. When I moved it to my 40G, I placed it even closer to the lighting and it did very, very poorly. They don't like high lighting. If you have the stock PC's in your BioCube, you can place it anywhere, but if you've upgraded the lighting, leave it towards the bottom half of the tank.