RBTA Hiding during day, Coming out at night?

I am still learning all I can about the nature of the BTAs... I've had my green one for a month now... it's doing fantastic!!! A buddy gave me a Rose BTA because it got bleached in a temp spike in his tank and he thinks I can bring it back. I am use to my green BTA that opens up nice during the day then gets slightly smaller at night. This little bleached RBTA will kind of half hide in a crevis (which it has not left since I got it BTW), then comes out more and opens up at night. I've only had it for about 5 days now I think... so I now it still has to get use to my tank. My green one never hid at all when I put him in my tank, he settled in a nice crevis and has not moved so far. So, just a little curious as to why the bleached RBTA is hiding... I know he isn't in super good shape... but to tell you the truth I have been able to bring him back healthier in just those 5 days compared to when I got him. He would barely hand onto the rock, he was shriveled and mouth gaping... but now he looks half decent except for the bleaching. Only thing is that he seems to get slightly smaller and half hide during the day when lights are on, then opens and even sometimes actually moved out of the crevis slightly at night.

 

Did you light acclimate it?