Same thing happened to me, I have a huge condi and it eventually lost every single one of its tentacles and I couldn't figure out why.
Well I sold the maroon, and now the condi has grown back all its tentacles and is back to what it was originally so I'm pretty sure it was the maroon doing it.
Here's a pic of them when I had the maroon, fish is about 4-5" and condi was over a foot fully open.