Filtersock maintenance

[Damdeno]

fairly new to hobby how frequent do you replace filtersock. Just placed some ick treatment and wanted to know if I should replace the sock to help get rid of any ick/ich treatment trace still in the filtration.

 

[Thrashed]

I change out weekly when I do water changes. Everyone has different opinions on when they should be changed. But I wouldn't go more than a few weeks without changing them out.