Seachem Purigen 250ml – Premium Aquarium Filter Media

Seachem Purigen 250ml is a premium synthetic aquarium filter media designed to remove organic waste and polish aquarium water to exceptional clarity.

Its unique macro-porous polymer captures soluble and insoluble organic impurities before they can break down and contribute to ammonia, nitrite and nitrate.

Ideal for freshwater and marine aquariums, Purigen offers extremely high organic-removal capacity and can be regenerated and reused when exhausted.

One 250ml container treats up to 1,000 litres of aquarium water for up to six months, depending on aquarium conditions and bioload.

Key Features and Benefits

• Premium synthetic aquarium filtration media
• Helps produce exceptionally clear aquarium water
• Removes soluble and insoluble organic waste
• Helps control ammonia, nitrite and nitrate by removing nitrogenous waste before it breaks down
• Extremely high surface area and organic-removal capacity
• Suitable for freshwater and marine aquariums
• Minimal impact on trace elements
• Changes colour as it becomes exhausted
• Can be regenerated and reused
• Suitable for canister filters and media chambers
• 250ml treats up to 1,000 litres
• Can remain effective for up to six months depending on aquarium conditions

What Does Seachem Purigen Do?

Organic waste continually accumulates in an aquarium from sources such as:

• Fish waste
• Uneaten food
• Decaying plant material
• Other dissolved organic compounds

As these materials break down, they can contribute to declining water quality and increasing nitrogenous waste.

Purigen selectively removes organic waste from the aquarium water before much of it can decompose.

The result can be noticeably clearer water and reduced accumulation of dissolved organic material.

Crystal-Clear Aquarium Water

One of Purigen's most noticeable benefits is improved water clarity.

It acts as a powerful water-polishing media by removing dissolved and fine organic impurities that mechanical filter media may not capture.

Purigen can be particularly useful in aquariums affected by:

• Yellow or discoloured water
• Dissolved organic waste
• High fish stocking levels
• Heavy feeding
• Driftwood tannins
• General water clarity issues

For best results, Purigen should be used alongside appropriate mechanical and biological filtration.

Helps Control Ammonia, Nitrite & Nitrate

Purigen does not work by directly absorbing ammonia, nitrite or nitrate in the same way as specialised chemical media.

Instead, it removes nitrogenous organic waste before that material can break down and release these compounds.

This can help reduce the overall load placed on the aquarium's biological filtration system.

A healthy aquarium should still maintain adequate biological filtration and regular water-quality testing.

High-Capacity Synthetic Filter Media

Purigen is manufactured from a unique macro-porous synthetic polymer.

Its microscopic pore structure creates an enormous usable surface area for organic adsorption.

This allows a relatively small quantity of Purigen to process a large aquarium volume.

The 250ml size is particularly suitable for:

• Larger aquariums
• Large canister filters
• Multiple aquariums
• High-bioload systems
• Heavily stocked freshwater tanks
• Marine aquariums

How Much Water Does Purigen 250ml Treat?

Seachem recommends:

250ml of Purigen treats up to 1,000 litres of aquarium water.

Depending on aquarium conditions and organic load, it can remain effective for up to approximately six months before regeneration is required.

Aquariums with heavier stocking or feeding may exhaust the media more quickly.

How to Use Seachem Purigen

Rinse Purigen before use.

Because the Purigen beads are very fine, place them inside a filter bag with a mesh size of 180 microns or finer.

Seachem recommends its The Bag filter media bag for this purpose.

Position Purigen where aquarium water is forced through the media rather than simply flowing around it.

Suitable locations include:

• Canister filters
• Filter media chambers
• Box filters
• High-flow areas of trickle filters

Good water flow through the Purigen will maximise its effectiveness.

Does Purigen Need a Filter Bag?

Yes, loose Purigen should be contained inside an appropriately fine filter media bag.

A mesh of 180 microns or finer is recommended because the Purigen particles are small enough to escape through coarse media bags.

Seachem The Bag is specifically designed for use with filtration products such as Purigen.

When Does Purigen Need Replacing or Regenerating?

New Purigen is pale or off-white in colour.

As it captures organic waste it gradually changes colour:

Pale → Brown → Dark Brown/Almost Black

A pronounced dark brown or black appearance indicates that the media is becoming exhausted and should be regenerated.

One major advantage of Purigen is that it does not simply need to be discarded when exhausted.

It can be regenerated and reused.

Regenerating Seachem Purigen

Purigen can be regenerated using Seachem's recommended regeneration procedure.

Seachem advises soaking exhausted Purigen for 24 hours in a 1:1 solution of water and regular unscented 8.25% sodium hypochlorite household bleach in a non-metallic container in a well-ventilated area.

Do not use scented, dyed, splash-less or unsuitable concentrated bleach products.

After regeneration, the media must be thoroughly rinsed and treated with a strong dechlorinator such as Seachem Prime according to Seachem's regeneration directions before it is returned to the aquarium.

Never place regenerated Purigen back into an aquarium if any chlorine or bleach smell remains.

Always follow Seachem's current regeneration instructions carefully.

Purigen vs Activated Carbon

Both products can be used for chemical filtration, but Purigen is not activated carbon.

Purigen is a specialised synthetic polymer designed primarily for exceptionally high organic-waste removal.

A major advantage is that Purigen can be regenerated and reused several times when maintained correctly.

It also has minimal impact on trace elements, making it useful across a wide range of freshwater and marine aquarium systems.

Purigen for Planted Aquariums

Purigen can be used in freshwater planted aquariums.

Its effect on trace elements is minimal, allowing it to remove dissolved organic waste without aggressively stripping the aquarium of important trace nutrients.

This makes it an excellent water-polishing option for planted tanks and aquascapes.

Purigen for Driftwood Aquariums

Driftwood can release tannins that give aquarium water a yellow or tea-coloured appearance.

Purigen is highly effective at removing organic discolouration and can significantly improve water clarity in aquariums containing driftwood.

Aquarists who intentionally want a blackwater appearance should consider this before using Purigen, as it may remove the tannins responsible for the darker water colour.

Product Specifications

Frequently Asked Questions

What does Seachem Purigen do?

Purigen removes soluble and insoluble organic waste from aquarium water, helping improve clarity and reduce the amount of waste that can eventually contribute to ammonia, nitrite and nitrate.

How much water does Purigen 250ml treat?

Seachem states that 250ml treats up to approximately 1,000 litres of aquarium water.

How long does Purigen last?

It can remain effective for up to approximately six months, although heavily stocked or heavily fed aquariums may exhaust the media sooner.

Does Purigen remove ammonia?

Purigen primarily removes nitrogenous organic waste before it breaks down into ammonia, nitrite and nitrate rather than acting as a direct ammonia-removal resin.

Does Purigen remove nitrate?

Purigen helps control nitrate indirectly by removing organic compounds before they break down and contribute to the nitrogen cycle.

Does Purigen make aquarium water clearer?

Yes. Water polishing and removal of dissolved organic impurities are among Purigen's major benefits.

Can Purigen remove tannins?

Yes. Purigen can remove organic discolouration caused by tannins and help restore clearer aquarium water.

Can I use Purigen in a planted aquarium?

Yes. Purigen has minimal impact on trace elements and can be used in freshwater planted aquariums.

Does Purigen need a filter bag?

Yes. Loose Purigen should be contained in a fine filter media bag of approximately 180 microns or finer.

Can Seachem Purigen be reused?

Yes. Purigen can be regenerated and reused when Seachem's regeneration procedure is followed correctly.

How do I know when Purigen is exhausted?

The media gradually changes from its original pale colour to dark brown or almost black as it becomes exhausted.

Can Purigen be used in a canister filter?

Yes. Canister filters are an excellent place to use Purigen because water can be directed efficiently through the filter media.