Picture posting is enabled for all :)
I add some jeyes fluid to the water and this helps prevent mould growth.
I prefer to keep the sand moist...To overcome this I give the sand a good soaking at the start of the growing season then cover it with a sheet of polythene.I find the polythene keeps the moisture from evaporating, i.e. condensates form on the bottom of it so the surface of the sand is always quite moist, which as goodlife says; it distributes the heat better.This is how I do it;http://www.thegardenersalmanac.co.uk/Data/Greenhouse%20heating/Greenhouse%20Heating.htm
It is the moisture which distributes the heat through the medium otherwise if the medium is dry it acts an insulator around the cable.
Quote from: daveyboi on March 08, 2016, 09:24:08It is the moisture which distributes the heat through the medium otherwise if the medium is dry it acts an insulator around the cable.You are a star.