Does Purigen Really Work? – Full Purigen Review!

Purigen effectively removes tannins from aquarium water, providing rapid and sustained clarity. However, its excellent performance comes at a higher-than-average price.

Most of my tanks have a slight yellow or brown tint due to bogwood releasing tannins into the water. Although this doesn’t bother me, I was curious to see if Purigen lived up to its reputation.

Here is my review of Purigen, based on my experience testing the product in a budget hang-on-back filter in a tank with a significant amount of driftwood releasing tannins.


  • Removed the bulk of the tannins within 24 hours.
  • Very easy to use and will fit in most filters with a carbon slot.


  • Higher price point than competing products.
  • The Purigen particles can crack if they dry out once wet.

Does Purigen Work?

Before And After Using Purigen
Before And After Using Purigen (24 hours)

It took approximately 24 hours for one sachet of Purigen to remove most of the tannins from my aquarium water, resulting in a noticeable improvement in water clarity.

While Purigen is more expensive than its competitors, its superior performance makes the cost justifiable. I am willing to pay a premium for a product that not only delivers excellent results but also does so quickly.

The clarity of the tank water continued to improve throughout the week, although the improvement was not as dramatic as the initial change observed between the first and second day.

Nevertheless, it is reassuring to know that Purigen is constantly working in my filter to passively improve water clarity without the need for chemical dosing or frequent water changes.

How Long Does It Take Purigen To Work?

My 29 Gallon Aquarium After Using Purigen
My 29 Gallon Aquarium 24 Hours After Using Purigen

Purigen started working immediately after I added it to my filter, with visible improvement in water quality noticeable after about six hours and impressive results after 24 hours.

However, several factors can influence the timeframe, so your experience with Purigen may vary.

I tested it in a 29-gallon (110 liters) tank with a 600l/h hang-on-back filter.

Changing any of these variables may affect the results, but I am confident that Purigen will remove tannins from your tank, even if it takes a bit longer.

For instance, using a 600l/h filter in a 40-gallon (151 liters) tank might slow performance slightly because the flow rate is the same, but the water volume is larger.

Conversely, using a 600l/h filter in a 20-gallon (75 liters) tank might improve performance as the flow rate remains the same, but there is less water to process.

How Do You Use Purigen In A Fish Tank?

Purigen In My Filter
Purigen In My Filter

Purigen is a beginner-friendly product, and most people can easily replace their carbon filtration pad with a bag of Purigen.

As shown in my photograph above, my bag of Purigen fits perfectly into a standard carbon filtration slot in a hang-on-back filter.

Since Purigen comes in flexible bags rather than rigid filter pads, you can adjust and fold the bags as needed to fit your filter.

Placing Purigen Into My Hang-On-Back Filter
Placing Purigen Into My Hang-On-Back Filter

Please note, the photograph above is for demonstration purposes only, using Purigen directly out of the packaging to show how easily it fits in a filter. Always wash your bag of Purigen under running water before adding it to your filter for use in your aquarium.

Seachem recommends placing your Purigen after the mechanical filtration in your filter.

This setup ensures that the mechanical filtration pads remove larger debris from the water, leaving the fine debris and tannins for the Purigen to focus on.

The filter used for this test is a budget 600l/h dual-compartment hang-on-back, with Purigen added to one compartment.

Technically, this reduces the water flow rate through the Purigen to 300l/h, which might slow its results. However, I don’t have any suitable single-compartment filters, making this the best available option.

Once the Purigen is in the required filter compartment, you are good to go and you can place your filter in your aquarium and power it up.

The Filter On My Aquarium
The Filter On My Aquarium

Final Thoughts

Purigen has proven to be an effective solution for addressing tannin-related water discoloration my aquarium.

The product demonstrated its capability by significantly improving water clarity within 24 hours and continued to enhance it over the course of a week.

While it comes at a slightly higher price point than some competitors, in my opinion, its superior performance justifies the cost.

Seachem Purigen Review


Water Clarity
Ease Of Use
Maintenance Requirements


Seachem Purigen is extremely user-friendly and can be integrated into most compatible filters in a matter of seconds. It removed the majority of the tannins from my aquarium within 24 hours, and considering its performance, I believe the price is reasonable.