Sources for PMDD

     In an earlier posting, Doug Skokna listed a source for PMDD trace 
     elements, with 4% Fe (Thanks Doug!)  :-)
     Miller Chemical & Fertilzer Co.
     Hanover PA 17331
     (717) 632-8921
     They have distributors nationwide.
     I got a list of hydroponics shops off the net, and called every 800 
     number listed (about 20) with no luck.  Finally, I found the chelated 
     trace mix with 7% Fe at a Canadian hydroponics shop (it seems to be a 
     Canadian product only; all the American shops I called carry liquid 
     trace elements and have never heard of the powdered form, and one in 
     Arizona tried to tell me that 7% Fe would be toxic).  I found it at 
     Coastal Growers Supply Ltd., Surrey, BC (604) 599-1778.  I'll bet 
     other Canadian shops carry it as well.  I got "The List" from 
     Some of the U.S. hydroponics shops are, like, really laid back, dude! 
     (I think I know who their regular customers are!) ;-)
     Here are the two formulas, for comparison:
     Fe 4%              Fe 7%
     Mg 5.4%            Mg 0%
     Mn 4%              Mn 2%
     Zn 1.5%            Zn 0.4%            
     Cu 1.5%            Cu 0.1%
     B 0.5%             B  1.3%
     Mo 0.1%            Mo 0.06%
     Co 0.05%           Co 0%
     Microplex has Mg and Co so it is a little more attractive in that 
     respect, but Microplex has 4% Fe while Coastal has 7%.  Coastal has 
     less of the other trace elements, except Boron.  Increasing the 
     Microplex dosage to account for the lowered Fe would also increase 
     the dosage of the other trace elements, which are already higher.  I 
     have no clue what effect this might have.
     The other alternative I found was to purchase each trace element 
     separately, and mix your own.  The liquid trace elements that I 
     commonly found were pretty diluted--the strongest I found was about 
     0.1% Fe, and most were a type of kelp puree.  Great for hydroponics, 
     but not in MY aquarium ;-)