30-04-2016, 06:47 PM
Very hard to do unless u have scientific equipment. What I can do though is base the filtration quality on the build quality. I know it's a bad way but I have always guessed that if the build quality is good it's unlikely they have cheaper out on the filtration media.
View my build thread here
http://306oc.co.uk/forum/showthread.php?tid=28072
http://306oc.co.uk/forum/showthread.php?tid=28072