Bests & Worsts Reviews from Amazon

Update: If you're going to buy Berkey, make sure you buy from an authorized distributor (contact the manufacturer, or buy straight from them). I bought from a seller that turned out to be unauthorized by the manufacturer, so now that the filters have failed, the manufacturer refuses to exchange them under warranty. Very funny. Why doesn't the manufacturer sell directly on Amazon? It's been 6 months since I got my first black berkey filter (with a Go Berkey). By now I've gone through 4 black berkey filters and they've all failed the red dye test after just 2-4 weeks of use! (except one filter which I didn't test initially and failed on the first test I did after about 2 months). The red dye test is recommended by the manufacturer to make sure that the filter is working well. I called the manufacturer and they told me to scrub the exterior of the filters that had failed with the green part of a Scotch Brite, rinse, re-prime, and test again, and all 4 filters failed the second test again. I've been very careful when I run the tests, I wanted to avoid bad results. The 4 filters that failed came from 3 different sellers, so I can't even blame it on they all coming from the same manufacturing batch. So how can I trust these darn things to safely filter unsafe water in a long emergency if they fail after maybe 20 gallons of tap water instead of the 3000 gallons they are supposed to be good for? I really wanted this thing to work.