"Nick Maclaren" wrote in message
...

I have this problem. I tried scrubbing with a broom, but I need to
get a lot of water on and the algae were pretty adhesive. Is there
a way of loosening them without damaging the polythene? I am inclined
to try dilute bleach.


Regards,
Nick Maclaren,

That's what we use, extended kitchen floor mop for the sides and a bit of
string over the tunnel with an old towel in the middle for the top (does
require cooperative wife!)

--
Charlie, gardening in Cornwall.
http://www.roselandhouse.co.uk
Holders of National Plant Collection of Clematis viticella (cvs)