IMO yes and no. It matters what kind of algae is growing on the skeleton. If its hair or red slime or something like that, the coral wont regrow. If its coraline or some kind of other hard algae, the coral will grow over it. I got a tiny bubble coral from a LFS for a few bucks and there is lots of coraline algae on the skeleton. A couple months later the bubble coral for 5-7 times bigger than when I first got it and the bubble coral grew over the coraline covered skeleton. HTH