The Custom Micro Mix Thread

burr740

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When I first started with the intention of cloning csmb at the same dose I was using then, 1 Lb of Mo was going to last.... 28,000 years!

The math was double checked, its in my journal somewhere
 

Phishless

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Well my scale rolled in today! .001 to 50gram.:D
So I had to pull out the box of precision weights and test.o_O

50g to 1g = golden with great repeatability.
Then everything down to 20mg got tested, just as good!
Everything less than 20mg went to hell on repeatability, but could be weighed just once right after turning on the scale.:mad:
I don't think my recipe has anything under 20mg but will have to check the spreadsheet.

Various compounds start rolling in tomorrow!:cool:
 
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burr740

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Anybody using Purigen? I know Greggz does, already told him about this. Here's what happened a couple weeks ago

The 120 has two canisters, each one has about 250 ml of Purigen inside. The bags are swapped out for fresh ones whenever I take one apart for cleaning.

So a couple of weeks ago, all of a sudden one day pantanal tops had gone pale with bright cherry red centers, clear sign it wasnt happy. Also mini limno, and something else too I dont remember.

Well nothing had changed in a few weeks (except for adding nickel which I'll get to later) and everything was crusing along very well with daily dosing of a .2 Fe blend.

Checked CO2, all good, racking my brain at this point, the only thing that's changed recently is I cleaned the Hydor two days ago and that certainly didnt do anyth......wait, the new bag of Purigen??

Ive always read it wasnt supposed to affect micros. Searched the Seachem forum, their official stance is "should have minimal impact"

Found some discussion on other boards with mixed opinions. A few folks were emphatic their plants did better without, the majority seem to dismiss the notion.

So anyway I removed the Purigen from every single filter, they all had it.

And lo and behold 2-3 days later the Pantanal and everything else was looking fine again. So...I believe it does have at least some impact, maybe on just a thing or two, and maybe unchelated makes a difference. IDK, just reporting what happened.

Update on the nickel. I'd started adding it to the micros about a week earlier. Couldnt really tell a significant difference but everything was growing really well.

Current recipe in ppb, dosing daily

Fe DTPA - 200
Mn - 90
B - 32
Zn -75
Mo - 1.3
Cu - zero
Ni - .5

Since removing the Purigen these last couple of weeks everything has really kicked up a notch. No issues to speak of with anything.

So either the Ni is soaking in making a big difference, or the Purigen, at least when brand new, was having a negative effect.

tifwiw
icon_smile.gif
 

Phishless

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Purigen is a dissolved organic scavenging resin.
I use it in all my tanks, capped soil will release tannin for a while etc....
Don't know if this can capture any metals, it is not like carbon.
 

Greggz

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Hey Joe, posted over there, thought I would here too.

So as usual, this is interesting.

You & I have discussed this, and as I told you, so far I have not seen the same correlation. I am running 200mg of Purigen in each of 3 filters, so quite a bit. I have not noticed any of the same symptoms after a change of Purigen, but then again I haven't been looking for them. Now I do have a fully stocked tank, so I might be getting more benefit from it.

My normal schedule is to clean one of three filters every two weeks, and add fresh Purigen at the time. So my plan is to skip adding Purigen for the next few cleanings, and see how things go. Kind of slowly wean the system and see where it goes.

I've been using it for so long, honestly I don't know anymore if it's doing anything or not. So we'll find out.

Right now I am 50/50 on the Ni or the Purigen. Could be either at this point. Interested in what others have to say
 

acinonyx

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I am using Purigen, but I don't think it is that important.

What I want to say is that this is very interesting observation, but it does not make sense to me from the chemical point of view. Purigen is positively charged (cationic) organic resin that binds negatively charged tannins (usually polyphenolic compounds). Micros are all cations so they would not be bound, but rather repelled. The only thing I KNOW is affected by it is nitrates (anions). Similar (or maybe even the same) resins are used to decrease levels of nitrates in tap water.

Also, consider the fact that Seachem is probably the only company using non chelated micros in their fertilizer. This would not make sense if it interacted with their Purigen.
 
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burr740

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I am using Purigen, but I don't think it is that important.

What I want to say is that this is very interesting observation, but it does not make sense to me from the chemical point of view. Purigen is positively charged (cationic) organic resin that binds negatively charged tannins (usually polyphenolic compounds). Micros are all cations so they would not be bound, but rather repelled. The only thing I KNOW is affected by it is nitrates (anions). Similar (or maybe even the same) resins are used to decrease levels of nitrates in tap water.

Also, consider the fact that Seachem is probably the only company using non chelated micros in their fertilizer. This would not make sense if it interacted with their Purigen.
Well they're selling Prime too which definitely interacts with unchelated micros

Isnt B an anion?

Deanna on TPT speculated that it might be interacting with the urea Im dosing.

Either way this is very interesting. I really have no idea what happened or why, just sharing the experience. But I will say the negative response was pretty dramatic, and sudden for no apparent reason. Seems a strange coincidence to happen 2-3 days after a new bag of Purigen. Not only that, but also for the symptoms to disappears over the next few days after removing it.

For the time being Im going to eliminate Purigen from the equation, because it's just one more unknown factor that might possibly be influencing things, however unlikely. Later on after some time has passed I'll re-introduce it and see if the result repeats.
 

slipfinger

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Very interesting!

I also use Purigen bags in all my filters.

I just changed the filter floss in my Hydor on Sunday and ended up removing the Purigen bag in the process, one because it was dirty and spent, two because of all the fines floating around the tank I wanted to add a second tray of filter floss. Normally like most I throw a regenerated bag back in the filter, but I was lazy last filter change day and didn't regenerate my spares. I will be changing filter floss again on the weekend and will add a regenerated bag back into the filter and watch closely to see if it has any effect on the tank.

Like most people and what Seachem wants you to believe, I was under the impression that Purigen has minimal to no effect on your micros.
 

acinonyx

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Well they're selling Prime too which definitely interacts with unchelated micros

Isnt B an anion?

Deanna on TPT speculated that it might be interacting with the urea Im dosing.

Either way this is very interesting. I really have no idea what happened or why, just sharing the experience. But I will say the negative response was pretty dramatic, and sudden for no apparent reason. Seems a strange coincidence to happen 2-3 days after a new bag of Purigen. Not only that, but also for the symptoms to disappears over the next few days after removing it.

For the time being Im going to eliminate Purigen from the equation, because it's just one more unknown factor that might possibly be influencing things, however unlikely. Later on after some time has past I'll re-introduce it and see if the result repeats.

Hmm, I suppose you are right. Then again, they specifically warn about adding micros too soon after using Prime, or do I recall incorrectly?

You are right, I forgot about B. That is the only other thing that Purigen could possible influence in my opinion.

Could it be that NO3 levels suddenly dropped after introduction of Purigen with high binding capacity? N starvation is another way how you induce coloration (and from my experience, it has quite an effect), plus pale leaves is how usually low N manifests, right? Or did I misunderstand the symptoms? (They were not 100% clear to me from your post.)

Anyway, I think you are right about eleminating Purigen for now. That's what I did in the case of my "nitrates disappearing" problem.

EDIT: I just realized Fe-DTPA is a pentadentate ligand, while Fe is in (+III) oxidation state. That means Fe-DTPA is essentially anionic (negatively charged) in water. But would it pull it out of the plants? That's a question...
 
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burr740

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Could it be that NO3 levels suddenly dropped after introduction of Purigen with high binding capacity? N starvation is another way how you induce coloration (and from my experience, it has quite an effect), plus pale leaves is how usually low N manifests, right? Or did I misunderstand the symptoms? (They were not 100% clear to me from your post.)

You're right that seems the most likely thing to have happened....on paper at least. Especially since a good bit of my N/NO3 comes from urea.

However, my NO3 levels are always off the charts. The latest test I had done using Hanna photometer showed 51 ppm, this was only a couple months ago at basically the same macro dosing.

So it seems unlikely that Purigen would've caused a big shortage in just a few days. Unless maybe it was zapping all the urea, and because the plants are adapted to having that particular source available it threw them out of whack for a minute.

EDIT: I just realized Fe-DTPA is a pentadentate ligand, while Fe is in (+III) oxidation state. That means Fe-DTPA is essentially anionic (negatively charged) in water. But would it pull it out of the plants? That's a question...

This is very interesting, I was not aware but now it sounds quite possible.

Surely it couldnt pull it from the plants, but I do find it hard to keep Fe levels up in the water column, and to avoid Fe deficiency symptoms in certain plants. Not all plants, just a handful of "usual suspects" that will quickly go south if Fe gets low

Another interesting result from the recent Hanna test I mentioned, Fe levels in the water column at the end of a week's dosing were .051 ppm. I would have to go back and look exactly what I was dosing, but it was somewhere close to 1 ppm total for the week, all dtpa. So either the plants were using one helluva lot or something else was happening to it
 

acinonyx

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You're right that seems the most likely thing to have happened....on paper at least. Especially since a good bit of my N/NO3 comes from urea.

However, my NO3 levels are always off the charts. The latest test I had done using Hanna photometer showed 51 ppm, this was only a couple months ago at basically the same macro dosing.

So it seems unlikely that Purigen would've caused a big shortage in just a few days. Unless maybe it was zapping all the urea, and because the plants are adapted to having that particular source available it threw them out of whack for a minute.

Yeah, could be either N or Fe problem in my opinion. I quickly googled the adsorption capacities of such resins and Purolite resins should really not be underestimated. Apprently, some of them can adsorb up to 82 mg (NO3) per 1 g of resin. (Purigen is probably some kind of a Purolite, not sure which one exactly.) See the papers:

https://link.springer.com/content/pdf/10.1007/s13762-014-0510-6.pdf
https://ac.els-cdn.com/S18761070163...t=1515596945_916f0efecce692895d6fe2cd5f99262e
https://ac.els-cdn.com/S13815148060...t=1515596704_8f182de729160d7cd0beca58db648f2e

EDIT: Now that you've brought up the Fe topic and you have the Hannah spectrophotometer, would you be willing to do one simple, yet intereseting experiment, Burr?
 
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fablau

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But, I think your tank is sucking Fe disproportionally indeed. I measured Fe in my tank before the last water change, and I measured 1.4 ppm (!!), and as you know, I was dosing less than you (with the exception I perform 50-60% WC every 2 weeks)... After 60% WC, I measured again and Fe was 0.7 ppm? I also use a Hanna photometer. So, clearly Fe accumulates in my tank. I use Prime after WC, but I don't use Purigen... I will give more details this weekend, as soon as I have completed my first week of super-crazy-high micro dosing ;)
 

fablau

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@burr740, I think your tank is sucking Fe disproportionally indeed. I measured Fe in my tank before the last water change, and I measured 1.4 ppm (!!), and as you know, I was dosing less than you (with the exception I perform 50-60% WC every 2 weeks)... After 60% WC, I measured again and Fe was 0.7 ppm? I also use a Hanna photometer. So, clearly Fe accumulates in my tank. I use Prime after WC, but I don't use Purigen... I will give more details this weekend, as soon as I have completed my first week of super-crazy-high micro dosing ;)
 
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burr740

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EDIT: Now that you've brought up the Fe topic and you have the Hannah spectrophotometer, would you be willing to do one simple, yet intereseting experiment, Burr?

I'd love to but the hanna is not mine, have to send it off to a guy. May can still work it out though, what is the proposed experiment?

And I can see it now, gonna wind up buying one of those damn things....
 

acinonyx

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I'd love to but the hanna is not mine, have to send it off to a guy. May can still work it out though, what is the proposed experiment?

And I can see it now, gonna wind up buying one of those damn things....

Well, what I noticed in my drop test for Fe is that the longer I wait for the color to develop (in span of several hours), the darker it gets. The principle of the test is formation of a complex between Fe(+II) and phenanthroline to give a purple complex which is then measured. Now I am not sure what Hanna uses but I assume it's the same (it's the most common Fe determination). The problem is, Fe-phenanthroline complex is relatively weak compared to Fe-DTPA for example. Long story short, the iron in Fe-DTPA has to go through the struggle of being reduced from Fe(+III) to Fe(+II) (Fe(II)-DTPA is about billion times less stable than Fe(III)-DTPA), then dissociate from DTPA and associate with phenanthroline. So there is a lot of equilibria and stuff going on and it seems to take quite a bit of time.

Basically I wanted you to take reading of Fe at certain time intervals after mixing the sample (i.e. 10, 20, 30, 60, 120, 180 ....overnight etc.. it will plateau at some point), that would give us an idea how much is the measurement time dependent.
 
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burr740

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Well, what I noticed in my drop test for Fe is that the longer I wait for the color to develop (in span of several hours), the darker it gets. The principle of the test is formation of a complex between Fe(+II) and phenanthroline to give a purple complex which is then measured. Now I am not sure what Hanna uses but I assume it's the same (it's the most common Fe determination). The problem is, Fe-phenanthroline complex is relatively weak compared to Fe-DTPA for example. Long story short, the iron in Fe-DTPA has to go through the struggle of being reduced from Fe(+III) to Fe(+II) (Fe(II)-DTPA is about billion times less stable than Fe(III)-DTPA), then dissociate from DTPA and associate with phenanthroline. So there is a lot of equilibria and stuff going on and it seems to take quite a bit of time.

Basically I wanted you to take reading of Fe at certain time intervals after mixing the sample (i.e. 10, 20, 30, 60, 120, 180 ....overnight etc.. it will plateau at some point), that would give us an idea how much is the measurement time dependent.
Ah, I see (even though most of that went way over my head :) )

Yeah that's not gonna happen on my end. I have to pay the guy for each individual test, and besides that, I'd need to see this type of thing for myself before trusting the results really
 

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DTPA Fe will accumulate, ETDA, not so much, nor Fe Gluconate. I think it persisted for a few weeks(at least two) when we used a test kit some decades ago now, maybe mid 1990's. The issue then was the left over chelators potentially binding other nutrients.
We used this one then:
https://www.hach.com/iron-color-disc-test-kit-model-ir-21/product-details?id=7640216697

If you want to get into this more and really test and make your own:
https://books.google.com/books?id=b...#v=onepage&q=Standard methods DTPA Fe&f=false

Read some of the sample methods for the Fe iron packets and the time frames they use for the sampling test. Allowing more time is not part of the methods in most phenanthroline reactions.
Bottom of the page, Hach uses this method and states 3 minutes. Not whatever you feel like.........
https://www.hach.com/pocket-colorimeter-ii-iron-ferrover/product-downloads?id=7640445233

If you want 1 ppb resolution, then the TPTZ Reagent method might be a better solution, it's good from about 1-400 ppb. This uses a 30 sec reaction sample time.
Hanna's low range Iron kit uses this method, their high range uses the phenanthroline. They use the same time for measurement using the the high range reagent: 3 minutes.

See pg 67-68
https://hannainst.com/downloads/dl/file/id/1168/man83200_18_04_12.pdf

If you want to deviate from this, fine....those are standard methods for a reason.......but now you are looking for conclusions 1st, then finding data that supports it.
That's not how things are done. You need standards in your methods.

You should run a reference sample also, an upper and lower to assess the test methods accuracy..........using your tank water and add say 0.10 ppm, 0.100 ppm and 1.0 ppm. Make your standard curve.


Now from here, you can dry the plant materials and see how much Fe is actually in the tissue, plant trace metal analysis is not that costly.
So you have the water's content of Fe and the plant's tissue content, showing it actually got into the plant.

Then you measure wet/dry weights or measure stem length etc.
 

acinonyx

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Yeah, but this is exactly the problem. They are standard methods, they don't consider special scenarios such as the presence of strong Fe complexes. Those are usually dealt with during the "sample preparation" phase, but not in our case.

I will try to test it in the lab when I have some free time.
 
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