Interesting Zeolite/nutrient thread in SPS forum

[Habib]

Hi Boom,

Thanks again.

However, I found something, skimmed only through it, looks like we would not need to worry much about potassium and perhaps also not the other cations. Atleast if we are not interested in ammonia removal solely by adsorption.

http://www.cape.canterbury.ac.nz/web...ata/974REV.pdf

[Boomer]

Yes, tables 1 ,2 & 3 show there is not that much of a difference to worry about I was a little surprised.

[Randy Holmes-Farley]

Why do you suppose they did not test sodium?

[jfinch]

Wasn't the zeolite precharged with sodium?

[Habib]

Originally posted by Randy Holmes-Farley
Why do you suppose they did not test sodium?

They talk about sodium and the various placement of sodium in the affinty serie depending on the publication.

The way they did the experiment (batch process) and the initial form of the clinoptilolite (sodium form) each mol/L uptake of ammonia or other cation would displace sodium and add the same mol/L of sodium into solution thus changing the medium.

Based on the amount of ammonia concentrations used and the amount removed from solution it looks like that ammonia had a far higher affinity for the clino than sodium.

It even looks like (in a quick glance) that sodium has a lower affinity than magnesium in their experiments for the type of clino used.


I'm not sure if that was your answer?

[Habib]

Originally posted by jfinch
Wasn't the zeolite precharged with sodium?

Yes. You posted while I was reading that article and typing.

[Randy Holmes-Farley]

Yes, but my concern reflects the fact that sodium in seawater is so much higher in concentration than any of those other ions.

The experiment is easily done by putting in much more sodium than could come off.

[Habib]

Originally posted by Randy Holmes-Farley
Yes, but my concern reflects the fact that sodium in seawater is so much higher in concentration than any of those other ions.

The experiment is easily done by putting in much more sodium than could come off.

That's why I was initially (and still) interested in knowing how much higher the affity for ammonia is compared to the other cations.

I think it would be worthwile to obtain some clino and perhaps also the zeovit stuff, condition it with ammonia free seawater and then do a batch experiment by spiking with ammonia.

[Boomer]

Hab

Does this help ?

http://www.gsaresources.com/cationexchange.htm

From the same site

http://www.gsaresources.com/toc.htm


Just me reading some things;

Zeolites have a critical advantage as model cation exchangers in that their swelling is not significant and salt imbibition is usually very samell under concentrations commonly used to study their exchange properties.

----------------

This is illistrated by the observation that the presence of small concentrations of ammonia in solution can cause dramatic increases in cation exchange capactiy, presumably because the zeolite prefers the complex ions created by the presence of the ammine ligand (-NH3) over the orginally uncomplexed ions in solution.

---------------


In a zeolite ion exchange the rate controlling step is the so-called particle diffusion process. This means that the rate of exchange depends upon the diffusion of cations, water molecules or cation-water complexes, through the zeolite framework.

At very low external cation concentrations the rate-controlling step to zeolite cation exchange can shift to the solution phase. Now the rate of exchange is depenent upon progress through the Nernst Layer of orientated water molecules close to each zeolite partilce surface. This is called "film diffusion" and is easily recongnized as how the rate of diffusion is affected by the speed of agitation.

Randy

Yes, but my concern reflects the fact that sodium in seawater is so much higher in concentration than any of those other ions.

You would think that the Law of Mass Action would apply here

[Habib]

I did a few quick experiments with a zeolite , if I assume that the information from the supplier is correct and is actually zeolite and not something else.

The amount used was approx. 10 gram of zeolite per 100 milliliter of water so that would equate to approx. 2 pounds (1 kilo) per 2.5 gallons (10 liter).

It lowered the ammonia concentration in both tapwater and seawater.

The effect in seawater was much lower but still significant.

For both seawater and freshwater the time to see the effects was many hours.

I also measured nitrite and nitrate and it can be excluded that the decrease in ammonia was caused by transformation to nitrite or nitrate.

I can't exclude that the observed decrease in ammonia was due to incorporation into bateria because neither the waters nor the zeolite and containers were sterile and also not the set up.

However, the samples using zeolite were compared with controls.


Since they were just quick experiments I would not feel comfortable to give the amounts of ammonia removed.

[invincible569]

Habib, thanks for running this quick test. So it does what people have been saying. Thats good to hear.

[Randy Holmes-Farley]

The amount used was approx. 10 gram of zeolite per 100 milliliter of water so that would equate to approx. 2 pounds (1 kilo) per 2.5 gallons (10 liter).


How large was the ammonia drop? That is one hefty load of zeolite. My new 90 gallon tank would, at that rate, use 72 pounds of zeolite.

[slow_leak]

Both links of the analysis are dead

[kennyangel]

This post isn't off topic, yet related:

I've been told that there is a thread here on Reef-Central where someone uses only one of those "Potions" sold by Thomas Pohl and still is receiving "good" results (brighter corals with less zooxanthellae).
An analysis of this liquid has shown that there is some kind of weed-ex in it wich will simply kill algae.

I don't claim this to be true, for it was just a rumour about a thread, but I wasn't able to find such a thread. If anyone knows about it please drop me a line.


On Topic:

Regardless what Zeoliths do in saltwater environments it might just be that Thomas Pohl has experimented and discouvered a method that "somehow" works, modified and eventually brought it to the market. It may well be that he doesn't know what's happening at all and that indeed the zeoliths are a futile fragment remaining from a trial and error analysis.
This is only speculation of course. You can reach incredible colourful corals with his system and that is what counts to some extend.

[gtrestoration]

I remember claims of Al, Fe and urine but not a weed killer unless is was in jest and I just ignored it (but I doubt that could happen ).

SteveU

[Randy Holmes-Farley]

Regardless what Zeoliths do in saltwater environments it might just be that Thomas Pohl has experimented and discouvered a method that "somehow" works, modified and eventually brought it to the market. It may well be that he doesn't know what's happening at all and that indeed the zeoliths are a futile fragment remaining from a trial and error analysis.
This is only speculation of course. You can reach incredible colourful corals with his system and that is what counts to some extend.

Perhaps. I personally wouldn't add something that I did not understand how or why it worked, unless I had great trust in someone who did, or I had an overriding interest in the observable effects (like coloration) regardless of other possible effects.

[Heinz]

Originally posted by kennyangel
some kind of weed-ex

2.4D or round up, i should have known
or maybe Basagran, hmmm, there are so many to chose from

[invincible569]

Originally posted by Randy Holmes-Farley
Regardless what Zeoliths do in saltwater environments it might just be that Thomas Pohl has experimented and discouvered a method that "somehow" works, modified and eventually brought it to the market. It may well be that he doesn't know what's happening at all and that indeed the zeoliths are a futile fragment remaining from a trial and error analysis.
This is only speculation of course. You can reach incredible colourful corals with his system and that is what counts to some extend.

Perhaps. I personally wouldn't add something that I did not understand how or why it worked, unless I had great trust in someone who did, or I had an overriding interest in the observable effects (like coloration) regardless of other possible effects.

That's the difference in human personality. Its like a company who is on the cutting edge of technology.. they may lose or they may win from it.

[Randy Holmes-Farley]

Yes, although you can be cutting edge, and still have your clients know what the product is, even if you do not know all there is to know about how it works.

In my field, pharmaceuticals, that is a hallmark that has made the industry successful in moving away from snake oils.