Since you once again have no idea what you're talking about, I'll go ahead and post the correct info. Just so you're up-to-speed, read this article about chelating agents:
http://www.buzzle.com/articles/the-importance-of-chelates-in-plant-nutrition.html
As you now know, chelating agents aid the plant in absorbing trace elements like Iron, copper, Manganese, and zinc to name a few. EDTA is most commonly used chelating agent. Higher quality grades of fertilizers also contain DTPA and fertilizers that include ethylenediaminedihydroxy-phenylaceticacid, denoted as "EDDHA" beside iron on the label are the highest quality fertilizers. Fulvic acid also acts as a natural chelating agent.
The article's summation:
Lets look at the GH nutes now, shall we?
Manganese EDTA
Iron DPTA
Iron EDDHA
...and when using some of their additives, you'll also get your fulvic acid.
So to correct your post, GH uses a variety of chelating compounds including the highest quality compounds available, which happen to be the SAME ONES THAT AN USES.