Purigen is it magic?

[Reef.]

Purigen, anyone think it’s a waste of space?
I don’t understand how this stuff is meant to last months in the tank and can be renewed with a washing of bleach? Where does all the stuff it’s filtering out go? Its not like it grows in size over the months, and how does a bit of bleach rid it of all this stuff it’s been filtering out of the water?

 

[Soren]

Purigen, anyone think it’s a waste of space?
I don’t understand how this stuff is meant to last months in the tank and can be renewed with a washing of bleach? Where does all the stuff it’s filtering out go? Its not like it grows in size over the months, and how does a bit of bleach rid it of all this stuff it’s been filtering out of the water?

According to Seachem's description, Purigen is a macroporous synthetic polymer. The pores trap particles from the water causing discoloration over time. I assume the bleach helps in breaking down the trapped particles to allow for rinsing them out in order to recharge the Purigen pellets.

I have no experience with using it yet, but I have bought some to include in my setup that is in-progress. It seems like a good idea, especially since it can be recharged. Basically, it seems to be a filter for smaller particles than will be captured by typical mechanical filtration means such as a roller filter or filter sock.

 

[DrMMI]

I use it in my freshwater tank inside my canister filter and it's awesome at keeping my nitrates down.

 

[Reef.]

So along the lines of a skimmer...you can see what the skimmer is removing over the life time of Purigen that would be a worthwhile amount, but microscopic particles that Purigen can hold, I’m just can’t see how it does what it says it does and remove any significant amount to lower nitrates or PO4 causing particles.

 

[rmurken]

Lol purigen. I run it religiously in my FW and reef tank. Why? Because I love the idea of little resin beads magically taking nitrogenous who-knows-what out of the water. But mostly just because it seems cool and can’t hurt.

The flip side of this is that Seachem’s cryptic, hype-y marketing-speak, which is loaded with spin to begin with, is especially unfathomable with Purigen. I’ve read it all and I still don’t feel like I understand exactly what it does.

But I do know it gets dirty over 6-8 mos in my low-bioload reef tank, and over 6-8 weeks in my planted FW tank (probably mostly because it has a chunk of tannin-rich driftwood in it).

I have a love-hate with it. Clearly it’s a cool substance that does something positive. But exactly what that is, and how strong an effect...we simply don’t know.

There was a great thread on another forum where some people were experimenting with various strong base anion resins (I think strong base...might have been weak)—as I recall they had some success replicating the organic scavenging that purigen seems to perform, but ran into issues and never found an exact match.

So it seems like it’s some form of a strong base (?) anion resin that will grab big (I guess negatively charged) organic molecules.

Also the bleach regeneration is impossible to figure out. Obviously the chlorine is necessary to oxidize the organics off the beads. But is anything going on with the hydroxide (it possibly being a strong base anion resin and all)?

I guess an experiment might be to test the pH/hydroxide concentration of the recharge solution over the course of a recharge.

One clue is that they’ve gone back to recommending that you soak it in neutral regulator (a phosphate buffer) after regen and before putting it in a FW tank. I skip that step without issue. But things that make you go hmm.

Bottom line of this stream of consciousness is that I love to hate to love purigen and cannot resist the siren call of a mysterious organic-scavenging resin. It is my favorite commercial conundrum in the hobby. Drives me nuts.

 

[Frogspon]

its a good alternative to carbon. just polishes water really. not sure i'd risk bleaching it just because It's cheap enough to replace it.

 

[rmurken]

its a good alternative to carbon. just polishes water really. not sure i'd risk bleaching it just because It's cheap enough to replace it.

I’ve done the bleach recharge many times without issue. As long as you do the soak in a really strong solution of Prime or Safe or thiosulfate or whatever. I think people run into issues when they mess that step up. Myself, after the dechlorination, I rinse it, let it sit in a few oz of water for a few hours, and then test it for chlorine just to confirm it’s safe.

For FW there may be post-regen pH issues (I guess alkalinity from the hydroxide part of the bleach?), but I use it there too, and have never had much of a spike.

 

[Reef.]

Did a water change, didn’t replace the Purigen, renewed the carbon and I can not tell the difference in water clarity, the water is as clear as it ever was, think I’ll stop using it, as I can’t see it removing enough organic waste to make it worth keeping for that reason alone.

If anyone has any real life experience where this stuff has made a difference please say as I have a tub needing to be used up, I would like to think it is doing something good for the tank, not just taking up space and collecting detritus.

 

[rmurken]

Did a water change, didn’t replace the Purigen, renewed the carbon and I can not tell the difference in water clarity, the water is as clear as it ever was, think I’ll stop using it, as I can’t see it removing enough organic waste to make it worth keeping for that reason alone.

If anyone has any real life experience where this stuff has made a difference please say as I have a tub needing to be used up, I would like to think it is doing something good for the tank, not just taking up space and collecting detritus.

Lol. You’re probably fine without it. The only difference it has ever made for me is in my curiosity about (1) WHAT DOES IT ACTUALLY DO; and (2) WHY DO I FEEL COMPELLED TO USE IT.

Pretty sure my reef and FW tanks would both be 100% totally fine without it. But the marketing is soooooooo goooooooood.

Muuuuuuuuuust haaaaaaaaaaave.

 

[mdb_talon]

I dont use it, but this is not at all uncommon. Carbon does not grow in size yet we know it can clean water. Gfo does not grow in size yet it removes phosphates. Remember the things it is removing is measured in ppm or ppb. It can remove a lot without it adding up to anything visible.

 

[Reef.]

I dont use it, but this is not at all uncommon. Carbon does not grow in size yet we know it can clean water. Gfo does not grow in size yet it removes phosphates. Remember the things it is removing is measured in ppm or ppb. It can remove a lot without it adding up to anything visible.

Good point but many say carbon is exhausted within days if not a week, and same for gfo that can be exhausted within hours, so you make a good point but also support mine, how can this stuff last months and months and also be recharged with bleach to go on again for another few months, as far as I understand it, bleach does exactly that, it bleach’s what it comes into contact with, does that remove stuff too? Or just colour it white so it looks clean?

 

[mdb_talon]

How the bleach works is way beyond what I remember from highschool chemistry, but I do believe it would be a chemical process that is breaking the bonds of the "junk" that is getting bound by purigen and so that junk is released when refreshed with bleach.

 

[Reef.]

How the bleach works is way beyond what I remember from highschool chemistry, but I do believe it would be a chemical process that is breaking the bonds of the "junk" that is getting bound by purigen and so that junk is released when refreshed with bleach.

thats just it, we don’t know so come up with a best guess to justify it.

Ive ran out of carbon, so I’ll use it in place of that, see if it does at least as good a job as carbon.

 

[rmurken]

thats just it, we don’t know so come up with a best guess to justify it.

Ive ran out of carbon, so I’ll use it in place of that, see if it does at least as good a job as carbon.

Tbh I have never heard of a problem that Purigen clearly solved. It doesn’t hurt anything, but what exactly it accomplishes for water quality is vague and mysterious. It removes nitrogenous compounds before the biofilter can oxidize them to nitrate. Just how much...who knows?

 

[Malcontent]

It's just an anion exchange resin optimized for tannins.

 

[Spare time]

It's just an anion exchange resin optimized for tannins.

Delete my comment reply

 

[Spare time]

I just wish they would clarify what nitrogenous waste they are referring to. It's not taking out ammonia, and there isn't uric acid in our tanks. Urea is produced in a tiny quantity by fish (though I don't know if this is all fish or not), but something that only removes urea would not be that valuable. However, people love the stuff

 

[Malcontent]

It is not an anion exchange resin. They specify this in their description

Do they?

 

[Adamantium]

To make things even more interesting, certain brands of Fluconazole specify you can use Purigen as a way to remove it from your system.

 

[Augus7us]

Lol. You’re probably fine without it. The only difference it has ever made for me is in my curiosity about (1) WHAT DOES IT ACTUALLY DO; and (2) WHY DO I FEEL COMPELLED TO USE IT.

Pretty sure my reef and FW tanks would both be 100% totally fine without it. But the marketing is soooooooo goooooooood.

Muuuuuuuuuust haaaaaaaaaaave.

I respect this comment a lot. Many would come on here and talk about how great the company is without any more a clue how this stuff works, than they do about splitting atoms. But you my friend, no shame in your game. Respect.

That said I did run it in my tank and thinking back I don't remember what sold me on it. Other than it was a british guy that recommended it and his accent made him very believable...