Hello! I have had a BTA in my tank for about 2~ weeks. It has opened up before, and is attached to it's location. But the location it has picked is hidden in a cave! 
How do I coax her out? I haven't been able to determine how large she is, even, because she's stayed in this cave. See attached photos.
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How do I coax her out? I haven't been able to determine how large she is, even, because she's stayed in this cave. See attached photos.

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