Aluminum Use...Again

I posted this last month and received no replys.  Can anyone help me 
out?  If pieces of aluminum were in constant contact with the fresh
water (that is, embedded in the substrate) in my tanks, would there be
any adverse side effects to plants or fish?  If so, could the aluminum
be coated in some manner to reduce or eliminate any harmful effects?

E. Keith Johnson
Johnson City, TN 
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             (  @ @  )
|        E. KEITH JOHNSON         |
| "Internaut, Aquarist & KE4ICG"  |
|    zekj2 at Access_ETSU-Tn.Edu     |
| East Tennessee State University |
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