On Sun, 2 Mar 2008 10:31:58 CST, Stylo
wrote:

As there are no fish and little chance of birdlife I don't mind using
chemicals etc. All ideas appreciated.

I'd simplify the filter a bit, so it would be more of a strainer that
is easier to clean and treat it like a pool, with pool (type)
chemicals. Even if you have birds, during warm weather, you can put
in a chlorine bleach at night and the birds aren't bothered by it the
next day. I have a yard fountain 30gal and I use a cricket bait
bucket to filter the pump and I use a bit of laundry bleach when
needed. The birds use mine and there is no way I can keep it clean
without brooming out the basins and starting over with a new batch of
water.
--
Hal Middle Georgia, Zone 8
http://tinyurl.com/2fxzcb