After much head scratching I managed to retrofit a new dual flush outlet valve in an old cistern. This saves about 9 litres of water for each half flush. Photos and some details at .
Suggestions and corrections welcome. I usually fix computer systems, not toilets. ;-)
Tom Worthington Director, Tomw Communications Pty Ltd ABN: 17 088 714 309 PO Box 13, Belconnen ACT 2617
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