Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Overpriced, doesn't last long at all...

This filter will maybe last you for 75 gallons if you are lucky, and that's on the higher end. Knowing this, the price should be half of what it is. If you pay $60-70 to initially buy the filter, you shouldn't have to pay $32 dollars (half the price of the filter) just for a new cartridge that works for less than half its advertised lifespan.I was using it in seemingly clear brook and stream water, not in mud, so I expect it to last a little longer.I have found that putting a coffee filter over the inlet tube on the filter will strain out some of the finer particulate, thereby giving you a little more life out of the cartridge. Although, I think that after spending $60 on a portable water filter you should not have to resort to this simply to get more life out of it.