I am worried for our flock because when we first started keeping chicken about 3 years ago, we had a galvanized water and read to put ACV in the water and did for quite a while, until we saw the rust forming in the galvanized water. And I read how it is toxic to the chickens. so immediately we got rid of it and switched to plastic waterers. Can there be left over residual effects in our chickens? As we have had a couple die recently from lymphsarcomas.