Here is my 2.5 gal "Greek Ruin" theme tank. Unagi's home, if she manages to stay alive...poor girl is getting ill I think. Got some greek columns and cut them again with the dremel. I just noticed her come up for air as I type this..but it seems..back to the bottom.
You said she is getting sick though, what are the pillars made of? If they had a special coating to make them aquarium safe and you cut through it, then they could be releasing harmful chemicals into the water. I'd say it's certainly worth looking into, even though they do look really cool. Good luck with her!