I picked up an amazing achillies from Pacific island aquatics a couple days ago. It's currently in Qt destroying pellets. The LFS has a powder blue that has been at the store for about a month. Any chance of them not killing eachother if they were added to the display at the same time? Tank is a 210g. I originally planned on just the achillies and still will go with that plan if the two won't likely work but powder blues are one of my favorites.