Q.My cereus was in a really warm room for 3 years, doing good and flowering once or twice a year. I moved it recently to another ho
use in a larger space less warm but still around 72 degrees and most leaves are pinkish red and seem to dry out. It’s on a south window but doesn’t get direct light, more like strong indirect light. Is it dying ?

Certified GKH Gardening Expert
Your plant apparently didn't take well to the change, but it's hard to say from here whether it's dying. I would give it a diluted, light dose of houseplant food and maybe a bit more warmth, if possible. You can summer it outdoors if it's warmer outside.
If any of the leaves look healthy, you can propagate a new plant.