With good water conditions, chalice are not hard to keep. Also, very cool when their mouths open and eat.
I do find that they are easy to keep. I had a difficult spot, I wanted to fill in. Basically, it's right below my filter output for an AquaClear 110. However, my chalice did the trick and likes it there. This is way up on the tank, so it's strong lighting.
I had a drop in PH, and right away, the chalice told me about it. So they are good indication, how my chemistry is doing.
wow didn't realize they can handle higher light. just got two peices not sure of what their type they are. put them in moderate flow, its been a week colors started lighten up but no feeding tentacles yet.