Trachyphyllia or something else?

[Kostas G.]

Hello

We got this one a couple days ago as Trachyphyllia, however I am not entirely sure wether it does is or not.
What do you think?

 

[cristata.reef]

Yes, that's a Trachy. You can usually tell by the outer skirt on the polyp that will appear to have a bunch of well-defined indented lines. This one is just a bit swollen, possibly hungry

 

[Kostas G.]

Thank you very much! I thought it was a Trachy just appeared unusual in the way it inflated/deflated and didn’t have much of these indented lines the first day. Possibly hungry as you said, in the first photo i had just fed it and it’s behaving more like a Trachy now..

Something else I wanted to ask is what causes tissue recession in a Trachy? The bottom of the skeleton of one of mine over the months has been a bit exposed compared to when I got it. It had hydroids growing there and it appears like these were harming its tissue there. Is that possible? Is there something else that would cause it? parameters have been
Ca 415
Mg 1380
Alk 9.1
Sal 1.026
NO3 0-2
PO4 3-6ppb P with ULR Hanna meter

All stable

Thank you very much in advance

 

[cristata.reef]

Could very well be the hydroids

 

[Kostas G.]

Hmm I see, thank you very much! They are mostly gone now from the Hermit crabs thankfully