Regal and Majestic would be difficult as they're more on the timid side... The longer you put them in isolation tanks, the more aggression may develop... If it was me, I'd get them all in a QT first... From the largest to the smallest would be Regal, Majestic, Flagfin, Blueface then Asfur... Once all of them are eating, put them together into the DT at the same time with all lights switched off... There will be aggression, but the aggression would be divided among the newbies... Sent from my SM-G935F using Tapatalk