I've never heard anyone use wood chips before (Well thats me), but give it a try if you wil, just make sure there no minerals present in it (not sure how you could test that though). Use well washed river/lawn sand (And I do mean darn well washed - there mud and all sort of minerals in it), or sandblasting sand like pondboy said. Your best bet would still be 50:50 LFS:Perlite or Peat:Perlite/sand though...try it out, and good luck, whatever descision you make. Its all trial and error, these things...well someone's got to do it, I rather it not be me - I've only got 1 VFT! [img]http://www.**********.com/iB_html/non-cgi/emoticons/wink.gif[/img]