Is Purigen worth it over carbon?

For organics and ammonia control, yes. Purigen is rechargeable and does not strip trace elements the way carbon can. Carbon is cheaper upfront and better for removing medication or odors.

How much do I need for my tank?

About 100 mL per 100 L (25 US gallons). A 100 mL bag suits a small tank; larger tanks need two or more bags or the 250 mL and 1 L sizes.

How long does it last?

Up to six months in a lightly stocked tank. In heavily stocked or high-organic tanks it can exhaust in weeks, shown by darkening beads and rising readings.

How do I recharge it?

Soak in a 1:1 bleach and water mix until the beads turn white, rinse, then soak in water with a dechlorinator until no bleach smell remains. Never skip the dechlorinator step.

Can I use it with medication?

Remove Purigen during most medication treatments, since it adsorbs the drug. It is safe to run again after treatment and a recharge.

Prices vary by store and size; the 100 mL was $15.79 at PetSmart as of November 4, 2026. Larger sizes cost more but lower the cost per liter.

Where is the Seachem Purigen Filter Media cheapest?

At PetSmart, for $15.79, 26% under what the other stores charge, as of our latest check.

Where can I buy the Seachem Purigen Filter Media?

6 stores we checked sell it, including PetSmart, SaltwaterAquarium.com, Walmart, eBay, Amazon.

Seachem Purigen Filter Media

Best price now

$15.79at PetSmartObserved at 1:15 AM

26% under what the other stores charge

Compared across 4 stores. Prices are checked against each store and labelled with when.

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Our take on the Seachem Purigen Filter Media

Seachem Purigen is a synthetic adsorbent resin sold as beads in a mesh bag for freshwater and marine aquariums. It removes organic waste, ammonia, nitrite and nitrate precursors, and many users report clearer water and stable readings. The 100 mL bag treats roughly 100 L (about 25 gallons) and lasts up to six months before it needs recharging. At $15.79 at PetSmart as of November 4, 2026, it is the lowest new price among the four stores listing it.