Urchin and dead Acropora

[Good Greef]

Hey Y'all,

I had a softball sized Acro colony that STNd when my ATO kicked on too long, due to calcification on my Osmolator's optical eye.

Because it was my fastest grower, I was bummed and decided to keep it in the tank for now. Fast forward 2 weeks, and of course the coral is starting to get some brown hairy algae on its dead skeleton. So out of boredom, I placed my purple short pin cushion urchin on it to see if it ate the algae. 24 hrs later, it looks like the urchin chomped away on 20% of the coral and left a trail of crumbled acro on the substrate.

Alas, any odds this Urchin has enhanced its palate to include expensive acros? Or is this normal for them to mow down dead skeleton?

[jestep]

I wouldn't rule anything out but guessing he's just munching on the algae and/or dead tissue.

[mFrame]

They scrape the rock when they're removing algae, so I would think that's what it's doing versus actively eating coral.

[Timfish]

Remember when a coral dies biological processes will start dissolving the skeleton so it will become more porous making it easier to fragment. Urchins can be pretty aggressive as they scour rock and coral skeletons to get all the algae including algae hold fasts. This helps put even more calcium back into the system and in the wild it creates clean places for coral larva to settle. The long spine black Diadem spp. urchins from the Caribbean do seem to be willing to switch to an omnivorous diet if they can't find enough algae. I've never seen any of the short spine urchins species available to us to bother live corals.

[Good Greef]

Thanks a bunch. Just making sure I dont leave any stone unturned.