The reason I ask about the approximate amount of bees is because you had ask about consolidating to a nuke. The queen should be laying if nectar and pollen are both coming in at a good amount. (As dictated by the amount of bees capable of tending to this brood.) If you do not have a robust amount of bees then the nuke may be a good tool as an aid for a faster buildup before winter. In my opinion, I would do just that, consolidate into a nuke. Open feed pollen substitute Ultra Bee, (because of SHB, you certainly can't afford that problem with an already weak hive), and sugar syrup to help as both pollen and nectar (or sugar syrup) is a must for building much needed brood.
In your case the sooner the better, fall is fast approaching. A nuke will make it easier for the bees to keep the box warm in raising brood if you do not have many frames of bees in this hive. A smaller space in your case will also make it easier for bees to fight off SHB and wax moths. A good way to feed this nuke in your case, (again in my opinion), is an in box frame feeder, (at least a gallon size with the built in ladder system to avoid drowning bees), or a hole cut in the top, the correct size (70mm) for an added quart or larger feed jar. I would also treat with OAV, (just in case and in due time), as this hive will need all the help it can get. Wishing you the best.
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