[Immunology] Counterstain for AEC AND BCIP/NBT

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Hi,
I want to do immunohistochemistry detecting two targets at the same
time. For various reasons I am going to use AEC as substrate for HRP
and BCIP/NBT as AP substrate. Now I am looking for a good
counterstain. Because of the AEC the counterstain has to work with an
aqueous embedding medium.
Has anybody a good idea? Thank you very much for your help in advance,
Sven