for sure it is not a dendro.
polyps, still, to me look like duncan, but the babies on duncans come off much higher just below the mother polyp. So maybe Tubastrea after all. Also, sounds like it has been around a while and fragged before which makes it more likely to be a Tubastrea also as duncans and dendros are, relatively, new to the hobby.
So, after all consideration and thought, I am going to go with a Tubastrea afterall.
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