I have two separate Formica (Serviformica) fusca queens with workers. Can I put them together in the same basin + farm set-up?
You could try to connect the two colonys but the chance of failure is very high. You should put both colonys in a fridge first and then put them in the same testtube. But as i said they will probobly kill each other. When you want very much you can try but you must know of the risk that both die eaven when at first nothing happens later on they can kill each other or the weaker one will be killed by the workers. I wouldn´t do it but it´s up to you.
When you want to do so first ask around how to do it best.
It will not work. Like was said, they will kill each other (probably) or the workers kill one.