Idk what’s going on

[Holland16]

My Zoa has been acting strange lately and I want to make sure it’s not being eaten or it’s not sick..
it looks like a few of the flowers have been eaten and this 1 zoa of the 5 that has been looking ticked for about a week now and I’m not sure where to start any ideas..
the last picture is what it is normally like

 

[MACHO]

what are your parameters? how long have you had them?

 

[Holland16]

I wanna say 7 months now for a while it was growing like crazy and everything is testing okay I had higher levels of nitrates before my water change but it’s returning to normal levels now I thought maybe the clown was ticking it off but it looks worse and worse every day.
I posted a picture of what it’s looking like today below
Thanks