Toilet cistern

Anywhere at all which sells plumbing bits, eg B&Q, Wickes, plumbers merchants...

Though personally I've always just cut bits of heavy-duty polythene to fit, without problems. If you buy a bespoke membrane you may well have to cut that anyway (if that's your problem), as the cross-section dimensions of syphons vary.

David

For the £4ish cost of a new siphon, is it really worth trying to repair an old one? Alan.

It is easy to change the diaphram as the top of the syphon can be removed without disturbing the inlet and outlet connections.

It is easy to change the diaphram as the top of the syphon can be removed without disturbing the inlet and outlet connections.

Have some of the family become heavy handed - as they got used to using a worn diaphragm. Now they are perhaps pulling too hard and damaging the replacement? Or is it a case that the replacement isn't flexing enough - or too much?

I bought 2 at a pound each from our local DIY shop - I was most surprised when he said they had them...

Geo

Go to Staples or any office supplies place & buy some of those translucent plastic folders with a press stud. Nice strong thick plastic - and a range of attractive pastel shades...

Any decent plumbers merchant stock them for a few pence But take the old one along as the are about 20 different shapes/sizes.