Sexy Shrimp Causing BTA to Close

[Tamale]

As title says. Is this normal? Sexy shrimp have started to walk onto BTA causing it to close up. It will open up again slightly after they get off. My rock nem does the same.

Is this just a matter of the nems getting used to the shrimp?

 

[Mr. Mojo Rising]

sexy shrimp will walk over everything, but everything opens up again once they move along.