is there any way to tell if your bioballs have been colonized? and will they colonize with water dripping over them like a wet dry?

Not sure of the timeframe, OF. but I believe it is over a period of a few weeks. I should think that water dripping over them would only help. How is your water testing out? That might be a good indicator.

BB's will colonize with water dripping over them but a small steady stream is best. you will know once they've been colonized, they change color