What should you use? I've always thought of petroleum jelly -- but realize that may deteriorate the o-ring. I've read other posts mentioning Silicon - but I only see that in an aerosol spray at Lowes. The pool stores sell Jack's lube -- but they are $10 for a very small tube - and I also want to lubricate other stuff as well - ( so I'm looking for something bigger).

Any recommendation for something at HD or Lowes? ( On a side note: be careful using keyword from this post in a google search at work - I was surprised at the results -- I guess I should have thought about it first :-)
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