You never did say what size tank you have them in. Size matters
but I usually wait till they're around 3" before adding dithers and IMO the best dithers were pure Midas. Not store bought midevils. Midas aren't as naturally aggressive nor belligerent like RD's they can take a beating very well and are great schooling fish. Not to mention just having another type of cichlid helps aide in pairing and spawning. Use a group of Midas, 4-8 and keep them smaller than the Festae.
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