No worries buddy. Most conventional fans do not draw many amps or wattage unless you're running very high speed fans such as san aces (5000rpm+). I have 4 gentle typhoons on each channel on my FC5v2 and it handles them with plenty of room to spare. I personally prefer to link fans to one channel, so that each of the controller knobs controls a different fan channel:
Channel 1: 4 Gentle Typhoons (Rad 1)
Channel 2: 4 Gentle Typhoons (Rad 2)
Channel 3: 2 Noiseblockers (Case Fans)
Channel 4: Cold Cathodes (Lighting)
The d5's speed control is pretty straight forward, all you need is a screwdriver to rotate the setting. I currently run mine on 4, as it provides adequate flow around my loop whilst minimizing noise. I suspect you will be able to run yours on 1 due to the simplicity of your loop - though when I ran mine on 1 it didn't even sound like it was on!