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Purigen Alternative

Joined
17 Mar 2012
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Location
Dorset
Is there a less expensive alternative that’s good at removing tannins? I’m currently using AC to keep the water clear but it only lasts about a month.
 
HI @Aqua sobriquet, Purigen is a pretty cost-effective and efficient way of removing tannins if thats what your after. Other than Activated Carbon and water changes I am not aware of any good alternatives. I am a moderate to heavy user of botanicals so once in a while when I think the water column get a bit over the top with tannins - when the tea is getting too strong so to speak - I throw in a Purigen bag in my HOBs.

Keep in mind that Purigen can be recharged (washed essentially) many times over. I use a mix of 50% regular bleach (not the non-stain or scented one) and 50% tap and let the bags sit in it for a day or so. If they are heavily strained (which is the case more often than not), I give them one more day with fresh bleach and water. Before using them in the filters I have them sitting for another day in dechlorinated water (tap with some seachem prime). After that, they are good for a month or so of usage (when storing the bags keep them in a zip lock bag so they wont dry out). I think I have repeated this 5-6 times with some bags. Some around here are more lenient - I believe @Wookii, when he was using Purigen, would reuse them many more times if I am not mistaken.

Cheers,
Michael
 
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I recycle Purigen in 1 to 3 % hydrogen peroxide.
Thanks, I always have 12% H2O2 to hand so I could dilute some for that. Probably safer than Chlorine Bleach?

Next question, any sources in the UK that are cheaper than others?

Edit: I’ve ordered a couple of bags on Amazon. 😉
 
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I recycle Purigen in 1 to 3 % hydrogen peroxide.
Hey @_Maq_ - do you find this works well? I noted that on Seachem's website in their FAQ they say:
FAQ: Can I use hydrogen peroxide, vinegar, or some other kind of "bleach alternative" instead of hypochlorite bleach?

NO.
We can only be certain that hypochlorite bleach will be both effective at regenerating the Purigen® and removable by Prime®. Any other bleach alternative has the potential to be ineffective or dangerous in the regeneration process.
If hydrogen peroxide does in-fact work, then I assume their statement is to push people towards using bleach, and then subsequently needing to use their product Prime? 🤔
 
Probably safer than Chlorine Bleach?
Bleach is incredibly harsh. I hate it. However, I've tried hydrogen peroxide once and it didn't work for me. Could have been the concentration. I've heard of others using it successfully - apparently @_Maq_ as well. Might depend on how dirty the bags are when you clean them - mine gets super dark brown almost black.

Cheers,
Michael
 
I’ll try the H2O2 first and if it doesn’t work I’ll resort to bleach. I did read somewhere though that the bleach in the US is stronger than the stuff in the UK?
 
I’ll try the H2O2 first and if it doesn’t work I’ll resort to bleach. I did read somewhere though that the bleach in the US is stronger than the stuff in the UK?
Yes, now that you mention that... I do not know the details, but I believe you may have some limitations in terms of what type and strength/concentration of bleach you can get your hands on in the UK.

Cheers,
Michael
 
I can't perform any professional analysis. I can't insist that hydrogen peroxide is just as effective as bleach. However, H2O2 is used for the same purpose, which is strong oxidizing effect. It would be used in water treatment instead of chlorine (and its compounds) because it's cleaner, BUT it's more expensive. Also, in case of overdosing, chlorine smell warns, while there's no warning from H2O2.
I can say that it makes Purigen repeatedly white, only slightly yellowish. There's one exception, though, which is iron. To dissolve and remove iron you need reducing agent. I've succeeded with oxalic acid.
Now, after many instances of using H2O2 my Purigen seems to be clean and effective. How much effective? Who can measure it? Me, not.
So, please, take my recommendations with reservations. It's an amateurish trick, no scientific truth. But I, like many of you, do believe that Seachem does not play fair, and if they can persuade you to do any thing using their products, they will dismiss all other ways for which Seachem is not needed. Such is my belief.
Practical advice: Sometimes it takes several days to see visible effect. In some cases, H2O2 has to be dosed repeatedly. Yet in the end (and with the abovementioned exception of iron) it's worked for me already many many times.
 
Practical advice: Sometimes it takes several days to see visible effect. In some cases, H2O2 has to be dosed repeatedly. Yet in the end (and with the abovementioned exception of iron) it's worked for me already many many times.
I am going to give hydrogen peroxide another try next time I I need to clean my Purigen bags.

Cheers,
Michael
 
I can't perform any professional analysis. I can't insist that hydrogen peroxide is just as effective as bleach. However, H2O2 is used for the same purpose, which is strong oxidizing effect. It would be used in water treatment instead of chlorine (and its compounds) because it's cleaner, BUT it's more expensive. Also, in case of overdosing, chlorine smell warns, while there's no warning from H2O2.
I can say that it makes Purigen repeatedly white, only slightly yellowish. There's one exception, though, which is iron. To dissolve and remove iron you need reducing agent. I've succeeded with oxalic acid.
Now, after many instances of using H2O2 my Purigen seems to be clean and effective. How much effective? Who can measure it? Me, not.
So, please, take my recommendations with reservations. It's an amateurish trick, no scientific truth. But I, like many of you, do believe that Seachem does not play fair, and if they can persuade you to do any thing using their products, they will dismiss all other ways for which Seachem is not needed. Such is my belief.
Practical advice: Sometimes it takes several days to see visible effect. In some cases, H2O2 has to be dosed repeatedly. Yet in the end (and with the abovementioned exception of iron) it's worked for me already many many times.
Does it need flushing with clean water after the H2O2 for it to come clean?
 
On another website a guy suggested that nappies likely contain a similar material to Purigen. Anyone looked into this?
 
Hi all,
a guy suggested that nappies likely contain a similar material to Purigen. Anyone looked into this?
That is the <"Aquarium Science"> review.
........ As a chemist well versed in polymer chemistry, based on the fact that the material swells in water and based on the decomposition products listed in the MSDS (no nitrogen compounds and no sulfur compounds), Purigen is simply a hydrophilic carboxylated acrylate polymer structure which gives a “macro-porous” surface for beneficial bacteria to colonize...........There are no special properties which such a plastic would have. It categorically is not an “organic scavenging resin”. The hydrophilic carboxylated acrylate chemistry is used in making baby diapers. This would appear to simply be one of the plastic resin bead feed stocks for making baby diapers.
I'm <"not qualified to pass comment">, although I'm going to imagine that it maybe <"pretty near the truth">. It would be fair to say he isn't exactly a Seachem fanboy.

From <"5.5.3.2.1. Prime, Safe and Ammonia">
.....Note that I admit I am decidedly biased against the Seachem Company. I can’t help it. The amount of “pseudoscientific bedazzlement” they put out on ALL their products is just nauseating. They mix real science in with simply impossible “snake oil” claims in a manner which is very misleading to “newbies” in the hobby. And they have threatened to sue me for “libel”. I do not like to be threatened......
cheers Darrel
 
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I guess the question is whether the author has evidence that Seachem have done zero tests. Perhaps he should have stopped at “my results show it doesn’t reduce ammonia”.
 
I tried the H2O2 technic. Was not impressed. Took 4-5 days for the Purigen to whiten up. Quick run down with pros and cons:

Bleach
Pros
:
  • cheap where I live: 46 baht/L => 1.3USD/L
  • Quick effect. 2 days max for complete regeneration. Could be less if Purigen not very saturated.

Cons:
  • Purigen needs secondary treatment for several hours with some Seachem Prime or similar product to remove all the bleach. This is critical. It needs to be rinsed after.

H202
Pros:
  • Purigen doesn't really need further processing after treatment since H202 will decompose as water and oxygen pretty quickly. A bath with warm water should suffice.
  • Cheap also where I live: 49 baht/L => 1.4USD/L - You can also find 6%, 12%, 35% and 50% here... I absolutely never recommend these high concentrations. Max would be 6%. That's already harsh enough. Remember that H2O2 is also used as an oxidiser in rockets. Also, it's used as a bleaching agent. I bleached my hair in my stupid years with H2O2. I looked like a dum ass with orange hair.

Cons:
  • Slower to clean Purigen
  • Not recommended by Seachem. This is highly debatable since they have an incentive for you to use bleach so they can also sell you Seachem prime after.
  • I am also concerned about the mechanical effect induced by the bubbling inside the polymer beads. No evidence on this just thinking out loud.

All in all nothing much against H2O2 other than the speed at which it acts. Next time I'll try with 6% H2O2 see how that goes.
 
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Pure sand (called quartz (SiO2)) can have the same effect on tannins like the purigen does - assuming it's rather rough so not coming from African desserts where the sand particles are rounded by winds etc. Idea is to have as much area available for bacteria and spores as possible when it comes to degradation of tannins.
 
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