Cadbury's dairy milk works fine for this, melted and mixed with some oil. We recommend using approximately 1kg of this and definitely thinned with oil, to allow the chocolate to flow well.
You may have plenty of chocolate left over - we have some chocolate moulds available for hire to go with.
KIT LIST: chocolate fountain base, power lead, inner spiral, outer tube, 2 x tier discs, instructions, box.
Please clean thoroughly before returning and put the plastic spiral through a dishwasher, if possible.