Mysterious Blenny Death

[ScubaSteve]

Today I lost my favourite fish. He wasn't like other fish I've had. He had so much personality and was, as much as a fish can be, a friend. Benny the midas blenny was the most friendly, excitable fish I've every seen. Every morning he'd wait for me in his green monti at the front of the tank, watching me sneak into the room, wiggling as he got super excited as I sneaked closer... and then would blast out from his house and go bananas when I finally went "Surprise!". Then he'd stop and look me in the eye, and you could tell he was checking me out as much as I was checking him out (having that fish look me in the eye is one of the most bizarre experiences I've had). We did this every day for two years.

That is, we used to until today...

This morning, no blenny when I sneaked into the room. I was immediately worried. I looked everywhere for him, couldn't find him. Checked all around the tank to see if he jumped, nothing. I looked and looked until I had to go, nothing. Got home in the evening, still nothing... until I was having dinner at 10 pm. I looked into the tank and my heart jumped when I saw a blenny bobbing his head up near one of my big colonies. Then my heart sunk as that blenny started to look pretty ghostly. As I got closer to the tank I finally realized what I was seeing. It was his skull and spine, stripped right to the bone, stuck on one of my colonies just blowin' in the current. Well... yeah... bummer.

I am particularly unsettled as to what happened to him. He has been fine for months, has showed no sign of stress or anything. And today, bam, gone. I've been racking my brain to see if I did something wrong.

-Water change on Saturday (25%, trying to get water chemistry back on par after my recent rebuild, parameters matched the tank perfectly, other corals and my goby are fine... so far)

-Fed frozen mysis to the tank on Sunday (?) (mysis have been frozen solid since March, goby ate some and seems fine... for now)

Everything else has been normal.

Possible causes:

-My tiger pistol shrimp that lives with my goby? (lives on the complete other side of the tank)
-Large electric blue hermit?
-Mystery predator?
-Bad mysis?

I am so confused and bothered by this...