A little tip which is incredible for the hiker owners.

I was told this about 3 yrs ago and it is amazing.

Wrap a coffee filter around the acorn prefilter and secure it with a ruber band and pump away. Its insane how much the coffee filter will keep out of your filter prolonging its life many times over.

I keep a bunch of bands and filters in my filter stuff bag.

Give er a try.

Hound