define- Coral Reefs are large underwater ecosystems made up of calcium carbonate structures made by hard coral polyps.
1. what is the difference between soft and hard coral
I've looked everywhere to find the difference but get different explanations like once I found an article saying hard corals have calcium carbonate structures while soft corals do not and another article say that soft corals have a bit of calcium carbonate in them.
2. do polyps die and another attaches to the skeleton to add on to it or do they just 'split' and grow into more polyps?
...or just paranoid?