Dechlorinators, micronutrients and EDTA

Hi All,

Sorry to bring up more fertilizer debate, but I have a few quesitons:

1) I currently use Tap water conditioner, which claims to dechlorinate 
and 'remove heavy metals'.  How long is this active after addition to tap 
water? Will this result in a serious reduction of micronutrients (Zn, Mo, 
Mn) added after dechlorinaiton?  Any dechlorinators which will not interfere 
with micronutrient fertilizers?   I remember hearing that Na thiosulfate 
was  an effective 
dechlorinator--does it work on choramines, and at what concentration?

2) Do other micronutrients (besides Fe) need chelation (ie Mg, Zn,Mo, Mn) ?  
For those of you that mix your own fertilizer, how does addition of 
non-chelated metals to a solution of Fe-EDTA affect their solubility and 
availability to plants?

I have been using a friends homemade micronutrient mix for 
a few months (he wishes to remain anonymous after the recent Dupla vs PMDD 
debate ;-) but am not completley satisfied with the results (he DOES get 
good results, however, so I'm keeping an open mind here).  Before I 
begin playing around with the recipe, i thought I might try the 3 Dupla 
ingredients as a positive control.  I'm haveing a 
hard time with the $50 price tag though.  So one question about Dupla:

3)  What is 'Duplagan' exactly?  I think George or Karen mentioned that 
it supplies Mg, can anyone think of a chemical reason not to add the Mg 
in with the daily drops, which contain mostly chelated iron?

George will frown on this, but I'm thinking of buying the tablets and 
then adjusting my 'daily drops' recipe accordingly.  I like the idea of 
adding nutrients to the substrate, and am not confident I could 
accomplish this on my own.

BTW, I really enjoyed the 'livley' debate on this topic!  Very good way 
to really learn about plant nutrition.

Thanks in advance,

Paul Bucciaglia