Planted Tank Guru
Join Date: Jul 2010
Location: British Columbia, Canada
I regenerate every 2-3 weeks when the Purigen beads get only light/medium brown, not dark brown, so that the beads return to their original off-white color more quickly in the bleach solution, and because I believe it extends their adsorption capacity for a longer period of time. I get more than a dozen re-charges without the Purigen losing its efficiency and needing to be replaced.