Speaking of eyes sunken in, while doing a water change, I was checking out the Luteus in the other tank and then looked at the spiney monster and noticed a fungus on his belly and his side fins looked chewed up and then something growing on them. He came out to eat and then I noticed his eyes were starting to sink in so I got a 10 gallon out and filled it up and now he is in there. He was always fighting with the Luteus so maybe he got hurt and I didn't see it till now. Hopefully he bounces back.