Id try just the one pair .. some hens are aggressive and might take to kindly to others in so close quarters .. . Problems iv had before when muling hens fighter destroying each others nests. one hen not letting other back to here eggs etc ... I presume your flight is 6 high by 6 long an 3 debt ... I'd split it in two .. so you'd have 2 flights .. 3 wide 3 depth and 6 high .. a hen in each flight and run the one cock to both hens .... thats what basicly mine but 4x4x6 .. one pair finches pair bullys 3 mulling pairs ... Iv seen cock finch thread one canary hen so far so fingers