the acan we are talking about (chalice like growth is Acan Echinata (thanx STANKYfish)
Chalice is fine near other chalice you could even fuse different types of chalice together
Acan Echinata will kill any other acan type or any chalice.
As for the acan you have,I would watch it for the day or 2 as it might be dying,hopefully not and if so it will eventually get its colors back.