On 12-0995, JERRY RUDOFF wrote to TOM WEISS:
 JR> Hello Tom..I have been following this conversation and have a
 JR> suggestion for cleaning.  Try liquid chlorine mixed with water.
 JR> This is the type of chlorine you get for swimming pool use.  Should
 JR> cost about 2 to 3 dollars for 5 gals.  Depending on the amount of
 JR> grung, about 1 part chlorine for 2 parts water should do it. Just
 JR> spray on, let sit of awhile, then rinse... Also kills bacteria and
 JR> fungus.  Birds love to lick the residue.  I've been using this
 JR> method for years with no harm to the birds.
Thanks Jerry,
I know that from personal experience (Dow Chemical; I'm an engineer) that 
chlorine  with water is corrosive to metals.  My concrete perch has a cad 
plated steel threaded rod in it for support.  This rod would surely corrode 
even in a mild chlorine solution.  I could try to keep it from the rod but 
concrete is porous and as such will allow the chlorine solution to reach the 
steel.  The steel upon reacting will puff up stressing the concrete and in 
time it will cause stress cracks in the concrete.  The effect would be time / 
concentration related and as such may take years ... but it will happen ... 
Bleach is my friend at this aviary .... except around metals ... unless I 
rinse right away ...
The residue the birds  are licking are salts from the chlorine.  IF they are 
organic (poop/food) salts they are not good to ingest.  Most insecticides and 
herbicides are halogen (Chlorine is one) organic salts.  Perhaps I know just 
enought to be paranoid ...
But Chlorine certainly would de-crude that sucker up but GOOD anyway!
===
 * Freddie 1.2.5 *
--- DB B2300sl/002493
---------------