Rinse before use. Use in a fine mesh (180 micron or less) filter bag such as Seachem’s The Bag™. For best results, Purigen® should be placed so as to maximize the flow of water through it. It may be used in a canister filter, media chamber, box filter, or any high flow area of a trickle filter. Each 250 mL treats up to 1,000 L (250 US gallons) for up to six months. Exhaustion is indicated by a pronounced discoloration of the beads to dark brown or black.
Soak in a 1:1 bleach:water solution for 24 hours in a non-metallic container in a well ventilated area and away from children. Use regular 8.25% hypochlorite household bleach (non-scented, no dyes, do not use a splash-less bleach). Rinse well, then soak for 8 hours with a solution containing 4 tablespoons of Prime®, or equivalent dechlorinator per cup of water. Rinse well. For freshwater use, soak for 4 hours with a solution containing 2 tablespoons of buffer per cup of water (Discus Buffer®, Neutral Regulator®). Original color and full activity should now be restored and Purigen® is ready for reuse. Caution: some slime coat products may permanently foul Purigen® and render regeneration difficult. Do not reuse if odor of bleach/chlorine is detectable. In case of doubt, soak beads in small quantity of water and test for residual chlorine with a chlorine test kit.