wot type of bio-bizz mix was it,ALL-MIX or LIGHT-MIX,im a first time i grower growing indoor and am using the ALL-MIX with no probs,although i did find a few chunks of soil that were bound together in lumps but a little bit of work with the fingers would break it down,i reckon its just down to the machining and length of time it may lie before being packed,didnt find clay in the ALL-MIX as it basiclly aint got clay in the mix