I think this depends on your water. I use my filters for 6 months at a time, every single day, and haven't noticed any effect like that. They do acknowledge s

I think this depends on your water. I use my filters for 6 months at a time, every single day, and haven't noticed any effect like that. They do acknowledge some people get a fishy smell on their troubleshooting page: https://www.zerowater.com/troubleshooting.aspx https://www.zerowater.com/troubleshooting.aspx