Unwaxed dental floss - where to buy?

[rossbaker]

I like dicko's solution above however I'd use a stainless steel hose clamp around the pressure releif valve housing instead. $1.50 from bunnings.

And the winner is... Hathro! (And Dicko cos his idea was basically the sameness). The hose clamp is a great little modification to make to the lid of a corny keg. Is a little bit fidly to tighten the Philips head on the clamp when it is on the lid, but I just tightened it enough so that it could be pushed on with a bit of force. Easily enough tension to hold a wet bag of hops and marbles. Thanks for the tip Hathro!