You should review this post. However, unknown if this will work for torch corals.
I did have the experience of a goniopora picking up a new zooxanthellae which quickly spread across the colony. Unfortunately the colony went from a light pink to a dusky reddish brown. I prefer pink but apparently the colony prefers dusky red. It seems to be growing even better now.
Anemones and other photosynthetic corals obtain their complement of Zooxanthellae from the water column in the wild. In many case , with stress Anemones can completely loose all of their Zooxanthellae. In case like this, we can jump-start the process by feeding them with live viable...
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