I take your point but my earlier argument still holds true. For a small organism that simply lives in a colonial structure it has no capacity to store water in order to survive even a day or two exposed to a the drying effect of the atmosphere. Small organisms can survive close to or within the water table. they can also live in the water stored by large organisms but neither of these solutions would compare to a coral forest on land. We therefore come back to the same problem in order to form something like a forest on land the coral would need to evolve methods to either capture and store or transport from the water table. To do either of these the coral would need to evolve complex multicellular structures with specialised functions just as plants do. Therefore the result of this would no longer be a colony of organisms like a coral but instead a single organism like a plant. If you combine that with its probable need to abandon calcium carbonate as its skeletal base and instead use cellulose or some hardened protein then one can see that you no longer have coral what you have is a tree.

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Note 1. All requests for planetary demolition must now be submitted in quadruplicate on form UX-565/B4 and be counter-signed by the assistant administrative officer for interstellar traffic calming - department QG-7. Subject to approval by the chief planning officer and the infrastructure development coordination sub-committee.