Instruct: Classify Amazon reviews into positive or negative sentiment
Query: I received a bad batch

This was the third pack of six I'd purchased over a few years. I installed one of the filters and noticed that its initial flow rate seemed much higher than the initial flow rate of previous filters I'd installed, and the water had a different taste. So I tossed the filter and installed a second one. Same high flow rate. Then I measured it's actual flow rate, which turned out to be 445 grams in 10 seconds. For comparison, I measured the 10 second flow rate of my faucet without the filter -- 914 grams. So the filtering was doing some filtering, but still it seemed too fast. So today I bought a 3-pack of the same filters (RF-9999) at Walmart, installed one of them, and immediately noticed that its initial flow rate seemed much more normal to me. I measured its 10 second flow rate at 301 grams. So yes, I definitely received a bad batch. Unfortunately, it's too late to return it.