On Sun, 6 Nov 2005 23:52:42 -0000, Rupert wrote:


You don't say whether the material is glass or plastic?

The greenhouse is glass and the conservatory roof is plastic.

I have tried adding household bleach to the water without too much effect.
Polishing with silicone is a good idea, but then one has accessibility
problems with reach and height.

As far as location, one has not always got a lot of choice.

I was wondering whether there was some effective commercial product
available, as this is quite a common problem?