BioTek Marine Nylon Filter Socks are quite possibly the best filter socks available anywhere. Made from a nylon material, these socks will last through dozens of cleanings. Your typical felt type filter socks have to be replaced after 3 or 4 uses. Our BioTek Marine filter socks can be easily washed out with a garden hose or a sink with a decent amount of water pressure. We’ve even used them by filling them about 1/3 of the way full with carbon as an affordable way to run carbon without a separate carbon reactor.