You should be able to just do one chain of flexwatt (double check that your length is over the recommended maximum length per chain or else you'll need to wire it twice). I have two chains of about 8ft on my rack (would have done one but I have two species on my rack) and it works fine. Flexwatt should be fine for melamine. However, any wood-type rack will have problems warping due to the humidity. I have a plastic rack and have no warping