Re: Problem Plant Tank to Paul Sears

> I have used the Chemi Pure for a long time, and neglected to read the 
> label after all these years.  Here is what I can tell you about it: It 
> removes CO2, copper, metal, ions, odors, all pollution, gases color, and 
> Phenol.  I do not know what Phenol is. 

"phenolic" compounds in natural waters are mainly humic acids.  Phenol 
itself looks like a benzene molecule with one -OH group stuck on it.  
The phenolic oxygen is quite reactive, and participates in a number of 
interesting reactions with other humic acid components.  I have a brief 
column on aquatic humic acids in the upcoming issue of AF.

The garbage list on the label is very generic and not very helpful in 
practice.  Yes, if I were to put a mixed bed ion exchange resin in water, 
it would remove all of the above, and all of the below.  And the water 
would become deionized water.  And things would then start to die.  Now, 
maybe they have been Extremly Clever in charging the resins, and what 
gets displaced from the ion exchange sites by the bad guys above is an 
approximation of what you want to have in the water.  But knowing what I 
do about the selectivity of ion exchange resins and the variability of 
municipal water supplies, I don't think that even *I* am that clever, let 
alone the people who designed this product.  ;0

In other words, they are sort of blowing smoke up the lower parts of your 

> It is also an ammonia and nitrate 
> scavenger.  An old Chemi Pure ad in FAMA 1988 states that it does not 
> remove trace elements and is the only filter medium that balances the 
> positive and negative charges with emphasis on the beneficial negative 
> ion.  

This is that part that is BS.  Ion exchange resins have higher 
selectivities for multivalent ions.  Most trace elements that concern us 
are at least divalent ions, and they will be adsorbed more quickly than 
monovalent ions.  The main reason they can make a claim like that is that 
in 1988 few hobs were in a position to measure trace elements...
> It is suppose to keep the pH at 7.0.  The reason I used it on this tank... 
> Because I am adding CO2 via the yeast/sugar method to water that already 
> has a very low buffering capacity.  For those reasons I thought it would 
> be good for the tank.  I do not understand why Chemi Pure which is 
> recommended for use in African Cichlid and saltwater tanks would take away 
> GH.      

Depending on what the resin was charged with, it could easily decrease 
the buffering capacity of the water further, expecially if you changed 
the chemipure.  I'm not familiar enough with the product to know what 
form the anion and cation exchange resins are.  I could set it up so that 
it targeted a pH of 7 several ways, some of which would leave the system 
with nil buffering capacity, some of which would bleed organic buffers 
into the system.
> > > Per advice from the list I am not using the Chemi-Pure at
> > > all now.

That was good advice.
>  Calcium and magnesium = the GH right?         


> I presented your questions about iodine to the person that told me to add 
> it to my tank.  Here is what I was told:  Iodine benefits all living 
> things as it does us.  

It benefits most living things in quite different ways than it does us.  
The main iodine requirement in mammals is for the production of thyroid 
hormone.  Other organisms, especially aquatic ones and ESP. marine ones 
use iodine and bromine in enzymatic reactions catalyzed by a class of 
enzymes largely absent in terretrial life.  

I see little reason to think that adding I2 to a planted tank would be 
more beneficial than adding I-.  There is a special case in marine reefs 
that I am looking into where there may be a slight advantage with I2.

> I would not be concerned about the copper since 
> using copper in plant tanks would be totally counter productive anyway.  
> The use of some molybdenum will further enhance the look of your plants.  

All plants require copper.  It is an essential trace element and 
should be present in all trace element products.

Paul wrote:

> > I have said this before, but it bears repeating:  If you put unknown
> > things into your tank or filter, the effects are unpredictable!!!  :)