I would advise against getting 2 sets of clowns in the same tank. it occasionally works but not all the time. They may get along for a few weeks or months but eventually one set will turn on the other. I had the same issue with my b&w's and my orange pair. They had to be removed the same day the aggression started since it was so bad. The one pair almost killed my b&w pair. It was viscous.
180g Reef - 60g Rimless Reef -90G FOWLR- 125g Malawi Cichlids- 40b REEF- 34g Fresh Planted-working on- 20L FOWLR- working on
I have a mix of many different saltwater fish amongst my tanks, but I love my Tangs most of all.