>>Question: What is the best way to feed old dark honey back to bees?
>very alert to the possible presence of undetected AFB spores. 

A relatively safe way may be to feed it to a swarm on foundation. Some 90% of any AFB spores will digested in the first hour.  Of course, the bees will try to deposit the honey as soon as foundation is drawn somewhat...

Waldemar

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