Introduction to Water Chemistry

I don't know alot about water chem. but I printed out the frist two articles and I'm gonna bring them to read at work (12 hrs. in a paper mill) I'll see what I can soak up from them!!!

 

[glow=Blue, 2, 99%]I'm sure you will have questions when you get back, david. Fire away!!! I didn't write the article, but chances are I've read it enough time that I can defend it like it wrote it. [smiley=grin3.gif]

See Ya Later !!![/glow]

 

What about EDTA ?

MDP

 

Alpha bet soup! - what is EDTA?

Thanks

 

EDTA = Ethylenediamine tetraacetic acid. It's a fairly complex molecule that has the ablility to Chelate or bond to positively charged ions like Calcium, Iron, Nickle, etc and hold them in solution. EDTA has a four ligand structure, meaning that it has for "arms" to bond with ions. EDTA's ability to chelate ions is fairly strong and difficult to break down. EDTA is also not very selective in terms of which ions it will bond with. In complexe chemical systems such as reef tanks a variety of reactions are possible and not all of them are favorable. I look at it this way. If Mom Nature doesn't use this mechanism in the ocean, we shouldn't either.

There's always a second approach to solving a problem.

 

MD --

I'm curious why you've asked about EDTA? Is it in a product that you have purchased?

E

 

I have always thought of EDTA as "removing" ions from solution, as things that are bound to it are not available for biologic use. We use it in medicine to bind toxic metals (ie lead) so as to minimize their effect on the body. I'm not a water chemist, but I would suspect that EDTA would bind the calcium etc. so as to not allow it to be used elsewhere (ie in coral skeletons).

 

Verbal--

You are absolutely correct.  By bonding with the ions, EDTA prevents the ions from being utilized in other reactions, chemical and/or biological, unless a great deal of energy is put into the system to breakup the organometallic complex.  When I refer to ions being "in solution" I mean that the ion or complex is water soluble, ie the metal-EDTA complex is not precipitating out of solution and forming a solid.  

With respect to Calcium, yes EDTA has quite an affinity for Calcium. Other ions are preferred, like Iron, but EDTA would definately make the Ca unavailable for your corals.

Great comment.

E

 

Excellent comments

 

Great stuff, thenks Eric!