[Histonet] Acid hematin

[raestask at grics.net]

I saw a Histonet post that Peggy Wenk had made concerning the recipe for alcoholic formalin for processing. She noted that you use the solution unbuffered.  How do you control acid hematin pigment in such a solution? 
We use a commercial alcoholic formalin “concentrate” that is diluted with alcohol and water prior to use.  It is supposedly buffered.  We have great problems with acid hematin.  Do you have any suggestions?  For preprocessing fixation, we make our own buffered formalin from scratch or from a concentrate and get biopsy specimens from veterinarians fixed in who-knows-what. 
Thank you very much, 
DW 
  
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