I used bio balls for my bio filter they kicked ass and were blue in big tub ..had a big container of em with water flowing through and exiting through a few hoses with the waterfall effect again ..plenty of aeration ...no issues ...was sweet setup lost pics when og went down...yeehaw them little catfish ate almost anything so I was working on modifying their died hoping for a better more complete poop...lol
Well, it was an interesting experiment at least, and you gained first-hand knowledge of a different grow style. That earns you green thumb kudos, my man. I'd give you rep if I could.