I bought one small and it has really grown just over 2 months. I have had some over a year that grew slow. I sold those back to shop or to someone else.
Elegances for me like direct light. Low to medium flow and no detritus.
Almost all will go through an initial "ugly" stage that appears to be them adjusting. They will shrink in, lose all tentacles and swell like a balloon. After a day or 2 to a few weeks depending how drastic it does, they will recover just fine.
I have just fed using indirect feeding with powder. I had more problems trying to directly feed with pieces.
I have a post in a thread of such an elegance where it recovered as well. They arent hard to take care of but just need a bit of understanding and watching detritus buildup. Great way to also know you need to clean the tank or around it lol.