I blame Jchillin for causing me to buy 2 new Aquaclear 50s (200s). The floss idea I got from JC and it really only works well with Aquaclear filters. I slapped them on my 2, 29 gallon tanks and stored my 2 Tetras 30s as backup filters. I took some of the Tetra 30 BioBags and used them as floss. So I put the floss over the sponge and put the biological media (ceramic nodules) over the floss. I had one bag I was using but I had made 2 more bags using Fluval rings that I had stored in compartments of other filters. Therefore I put in inoculated media on the 2 new filters.