My tank ran 2 years without filter socks of any kind, had so much debris circulating in the tank it was always hazy. I recently put on 200 micron filter socks and a 25 micron cannister filter cartridge. The first month my filter socks lasted 12 -15 hours. Now, that the water column is finally filtered out, I'm getting almost 2 days out of each of my filter socks! I'm ecstatic! You want a week? Wow! I'd be amazed if I got a week out of mine. I run it through a bleach cycle in the washer with cold water so as not to evaporate the bleach, then I rewash on a sanitize cycle, with no bleech. They continue to last up to 2 days for me. This week was the longest at 3 days per sock. I might finally be getting most of the particles out and moving to a normal. .