there was someone posted from a company called NCPM247.com who use an additive in their tanks i wrote to them regarding buying a sample but they didnt reply, i have done some research of my own and there are a lot of coatings that make the glass hydrophobic but these are time consuming to apply and cannot just be added to the tank therefore not practicable to us, there are companies in china that do a spray coatings to buildings so they stay clean the main component of these sprays is a chemical called Ti02 or titanium dioxide but i havnt looke into this any further as yet.
if you find the product i am sure it would be both time saving and water saving let us know if you do find the name of the product.
