I am wishing to combine 3 nucs into 1 deep box. Should I let the queens fight it out or should I make the decision for them. The nucs are from swarms Mick
Depends on how you are going to combine them. I wouldn't just dump them altogether at once, you might loose all 3 queens.
I would cage one or two queens with food and attendents, combine all at once, three days later, if they are queenright, kill the caged queens. Keep the caged queens out of the combined hive. If they kill their queen, you can introduce a caged one.