Reef Chemistry Question of the Day #233 Purigen Binds Which Inorganic Ions?

[Randy Holmes-Farley]

Reef Chemistry Question of the Day #233

Which of the following can bind directly to Purigen, based on Seachem's description of the product and how it works? List all that you believe can bind.

Seachem says:

" HyperSorb is an ion exchange resin, while Purigen has properties of both a scavenging and ion exchange resin. These products are anionic"

A. Phosphate
B. Nitrate
C. Calcium
D. Magnesium
E. Sodium
F. Chloride

Good luck!



















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[SEMA]

C,d,e,f? Just a guess. Mostly because i wanna know the true answer and why/how?

 

[MnFish1]

Would have to be C, D, E - but Purigen's paperwork states that it has little effect on elements or metals. Mostly organics.

 

[Randy Holmes-Farley]

Would have to be C, D, E - but Purigen's paperwork states that it has little effect on elements or metals. Mostly organics.

Yes, I've seen no data to support their assertion, but I'm not claiming the amounts are high or low, just that it happens.

 

[SDReefer]

Yeah, C, D, and E are all cations. It would reduce NO3 because it can bind to NH4 before it breaks down, but that's a secondary process.

 

[rkpetersen]

Based on this:

Purigen® is a premium synthetic adsorbent that is unlike any other filtration product. It is not a mixture of ion exchangers or adsorbents, but a unique macro-porous synthetic polymer

And this:

Unlike other products on the market which are simple ion-exchange resins, Purigen® is specifically designed to be an organic scavenging resin. When ion-exchange resins are filled to capacity by metals and other contaminants, Purigen® has barely begun to reach its potential. Purigen® generally ignores simple elemental compounds, having an extreme affinity for nitrogenous organics.

I would say:

None of the above.

(Sounds like it functions a bit like GAC, tbh.)

 

[SDReefer]

What's the answer @Randy Holmes-Farley?

 

[Randy Holmes-Farley]

And the answer is...

Which of the following can bind directly to Purigen, based on Seachem's description of the product and how it works? List all that you believe can bind.

Seachem says:

" HyperSorb is an ion exchange resin, while Purigen has properties of both a scavenging and ion exchange resin. These products are anionic"

C. Calcium
D. Magnesium
E. Sodium


An anionic polymer has a negative charge on it and it will bind to all positively charged ions to some extent. Seachem suggests it is provided as the sodium salt, and some of the sodium will swap for other positively charged ions. Seachem claims it is not primarily an ion exchange resin but rather one that binds organic matter. They do not reveal exactly what the polymer is, but it could be any number of different anionic and likely partly hydrophobic polymers. Crosslinked polystyrene sulfonate, for example, or a copolymer of it.