Thanks mate. Ive only used al foil on the cold tiles, then I have covered that with that stuff thats black on one side and white on the other. (ive forgotten what its called) I got it from the grow shop, so i guess its ok. The white reflects the light great. Any suggestions from anybody on what i should use on the shower FLOOR?? At the moment all i have is like thick sponge, worked great at first, but the weight of the pots has flatted it and im worried that they wont be breathing through the bottom holes or could even get mould into the dirt? Any suggestions from anybody would be fantastic