Two Cynidarian corals, any advice appreciated

[Reef.ductionist]

I have housed.these two plates for a month now, for the last few days I have noticed one is not expanding like the other. Here is a pic below. They are both getting the same flow.
Does anyone know what's going on or have any ideas as to why the one is not expanding like the other?
Thanks in advance.

 

[lakeviewink]

Maybe the upset one is female? Lol

 

[KSzegi]

I have two that do the same thing .... one large one that is almost always inflated with tentacles out. The other smaller one I've never seen inflated - but I've had it for over a year, still has good color and has grown. I just assumed that it was a different type.

 

[Reef.ductionist]

Hi KSzegi, thanks for replying. Are your plate corals in close proximaty to one another?

 

[KSzegi]

Yes they are - close enough to almost touch - so they are getting the same conditions as far as lighting and flow too!