I built a DWC hydroponics system the other day and it seems to be working just fine, but i'm concerned that my media isnt right... I heard that LECA works well and i havent seen it done any other way... but at the same time right now, i'm using perlite right out of the bag with a few river stones at the bottom of my culture pots to hold my plants... is this bad? should i change it? how do i go about changing my media without damaging my new roots??? any help or suggestions or pictures, links to videos, anything would be appreciated! thanks guys and happy growing!