Look on Ebay. A company on there, Blue Mtn Organics, sells some real good natural ferts. They filter & pastrize um. Then add good bacteria to afterwards, so they don't clog or stink. I got some and they are working great in a bubbler DWC system. Plus they are cheap, but not cheaply made. Good ingredients. If you, want big name stuff, Earth Juice is good, but has sediments (which can clog), Bontanicare is real smooth, clean stuff but expensive, around 16 bucks a bottle. The BMO stuff seems to be working just as good for about 4 bucks a bottle plus shipping. So, thats more than fair.