On Fri, 27 Apr 2007 21:00:12 GMT, "Alan Holmes"
wrote:


"Ford Prefect" wrote in message
.. .
I keep a couple of tropical fish tanks and was wondering if the waste
water after water changes would be benificial or harmful to garden
plants, seems a shame to flush 40l a week if it could be doing some
good in the garden instead.

Why on earth would you want to change the water at all?

He's talking about partial water changes, and you know it.