Thanks for the advice guys, keep it coming
They might be aright when small but once the firemouths get 6"+ it will be risky. Keyhole cichlids would be a safer choose. What about Red breasted acara.I'm surprised the firemouths don't go after the cardinals. Are they peaceful? I'm leaning towards maybe getting some keyhole ciclids, but those firemouths are nice.
Again, I love your tank! One of my favorites of the ones posted on this site.