Hi all, I have a question , how do you messure the CO2 level in a tank then you filter through peat ? All tabels I have seen say that they can't be used then you filter through peat. Regards / Hans Sandén Hans Sandén Rynnings väg 24 S-360 42 Braĺs SWEDEN ICQ#10674725 E-Mail hans.sanden at vaxjo_mail.telia.com Hamcall : SM7TKL Discus owner