Can Corals go dormant?

[Livebearer]

I have access to a nano set-up 3 gallons with live corals, but it has no filtration (circulation) with a heater at 77o will they go dormant or die off? This happens in a tidal change (stagnant tide pools left to bake in the sun.) I don't know if they're hard or soft corals though as I have not seen them in person yet... Please advice

 

[clownie]

They won't go "dormant" as long as they have proper lighting and proper water changes. I would say a cup a week on the water change. Check into what types they are and we can go further on care. HTH!