After doing a little searching and reading a few reviews ... it seems that the Zero Water system is great at removing solids but the water may end up smelling "fishy" after awhile. Also, it's designed to filter water that has already been treated against bacteria so it may not be a trustworthy filter system if removing bacteria is your goal. Also, the price for a Zero Water system is only $29.00 on Project Farm but it's around $45.00 on Amazon. Also, replacement filters look to be a bit pricy.
Does anyone have any experience with the Zero Filter? I personally use the Crown Berkey due to its ability to remove harmful bacteria but it's not great at removing solids. Perhaps using the Zero Water prior to using the Berkey could be the best of both worlds? Just speculating!!