UV Steril. & Photodegredation

I ponder getting a UV sterilizer for my 100gal, but have read some recent
posts about them degrading the iron we add for our plants.  Does anyone
know if you dose your tank daily with fertilizer, would the degredation of
the iron and other chelated elements by the UV ster. be enough to prevent
the needed uptake by the plants?  Put in a more simple way:  How long
would it take the UV ster. to break down the chelated elements in the
water column (assuming usage of PMDD or similar fert. used to achieve
levels suggested by Colin & Sears, flow rate through UV ster. is 3.5 tank
volume/hr, and 100gal total tank volume. :) if you stopped dosing the
tank.  50% gone in 24hrs?  More or Less?  Has anyone experimented with
this on their tanks?

Thanks in advance.


      <>< <>< <>< <>< <>< <>< <>< <>< <>< <>< <>< <>< 
      ><>   If only we could dream like fish...   ><>
      <><   then our souls would be free.         <><
      ><>                                         ><>
      <><   M.P..      pearlsco at u_washington.edu   <><
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