The acan is has more flesh- let’s call this meat. The Acan is the meatiest of all three , the echinata has about ¼ of the flesh of the acan, the favia’s skeleton is only covered with flesh, it does inflate but never as thick as the other two. Oh and the acan has distinct polyps. If you want to see the difference between the acan and favia feel free to swing by- I’m in Woodbridge.