I'm pretty positive you have a Acantopsis octoactinotos rather than a Acantopsis choirorhynchus
I really hope you have just the one and don't have it with small fish as
A. octoactinotos will kill small schooling fish if hungry (especially Neon Tetras and Zebra Danios).
his tank mates are a pair of german rams,2 different kinds of newts,swordtails,mollies,a chocolate gourami, and ghost shrimp. he was sold to me as a horse face and my swords have had quite a few babies and has bothered them.
Burrowing in large rocks like that can lead to cuts, this in turn leads to infections which inevitably lead to death.
Just because he's fine now and will bury does not mean he will stay like that. I would change the substrate to sand, or at very least...very fine rock.