In an effort to remove the buildup of surface slime and increase degassing I turned one of my Cascade 150's into a surface skimmer. The amount of skimming action can be regulated by how high the nylon sock is raised on the intake tube(last picture). The last section is a tight fit but it can be removed and a sponge added to the PVC as well.
I used 1/2"NSF-pw(for potable water) PVC piping-short sections of pipe, couplings, elbows, and an old intake tube extension from an Aquaclear HOB.(I never throw anything away...LOL)
Also one of my Wife's nylon socks and a couple rubber bands...the cost of doing that is unknown at this time..though I'm sure I'll hear about it from her
It covers the white PVC and looks alot better but also serves the purpose of regulating the skimming.
Total cost of project was under $5