I used to be a staunch advocate for diatom filters. I stopped using them due to all of the health issues from the use of diatom powder. Now I use filter socks for water polishing. I routinely run a 200 micron sock. For additional polishing, I'll temporarily run a 100 or 50 micron sock until the water is crystal clear. On my wood chewer tanks, I'll run a 500 micron sock to catch all of the sawdust. The sock filters use zero power. I just slip them into holding brackets at the outlet of the filter system.