I got rid of my bioballs. I have a 29g biocube and the bioballs were standard filtrations. I had no problems for a year and then I had unbelievably high nitrate levels. Nothing took them down. I gradually switched from bioballs to live rock in the back and I am much better off. So.. If you do keep them, I would think that you would want to at least rinse them off in some tank water. (but not in your tank!)