It's possible for corals and anemones to share colors via uptake/exchange of zooxanthellae, yes. Corals can uptake zooxanthellae from the water column (to my understanding, this is commonly done by broadcast spawned coral larvae; brooder larvae tend to take zooxanthellae from their parent colony; it doesn't seem to be very common in mature corals), so sometimes - fairly rarely in our aquariums - corals placed near each other may uptake a new strain of zooxanthellae and start changing to the color of their neighbor.
I'm not sure what conditions need to happen for this to take to place, but essentially the conditions would need to be at least somewhat more favorable for the new zooxanthellae so they could gain a foothold despite the coral's current zooxanthellae.
OrionN has used this concept of transferred zooxanthellae to help bleached anemones recover by feeding them a small tentacle from another nem to essentially inject zooxanthellae into the bleached nem.
Anyway, it's not common, but you can see examples of it below (I've seen a few more examples with corals, but I can't remember the threads - sorry); as is mentioned in the thread about zoanthids, though, sometimes the colors change without neighboring corals due to lighting conditions - both methods of change are possible; the lighting changes are more common in aquariums, but there are some clear cut cases of the change being caused by an added neighbor:
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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So I have a green hammer that’s been green for awhile. It’s over 3 years old. Started keeping it near some golden hammers as well. Last few months the green hammer has started to turn gold? Anyone ever seen LPS share color before?
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So my Maui Wowie Zoanthids are touching my Everlasting Gobstopper Zoanthids, the Maui’s are blue/greenish and the Gobstopper are pink. I noticed that the newest Maui Polyp has hints of pink, it looks a lot more pink in person, but if you look at the picture, you can see there’s quite a...
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