Filter socks are a critical component in maintaining water quality in aquariums. They remove suspended debris and detritus, which often lead to excess dissolved organics, nitrate, and phosphate when left unchecked. This makes Seachem Filter Socks an integral addition to any sump and overflow system. Seachem Filter Socks feature durable, welded seams and have a singed finish, which reduces wear and prevents release of fibers back into the water column.In addition to a 100 micron rating for exceptional particulate removal, they feature welded seams, which, unlike threaded seams of similar products, will not breakdown over time. They have a singed finish, which reduces wear and prevents release of fibers back into the water column. Finally, the plastic collar simplifies installation and easily fits standard sump fittings. Because Seachem Filter Socks have a 100 micron rating they will trap more debris more quickly that socks with a higher rating. Maintenance will vary depending on the demands of the system, but the best way to determine when cleaning is necessary is once the sock becomes discolored. This could take anywhere from a few days to a week. 10 x 30 cm / 4” x 12” (10 cm / 4” plastic collar)