The package arrived on time and the berghia are all doing well. I acclimated them for over two hours and placed them in a safe spot in the tank. A few were eating while acclimating in the bag. They all have moved on and found hiding spaces, so ...
I just pipetted the critters into the tank. It looked like they went to work so I think we acclimated and transported well.
Thanks for your help. I look forward to the result over the course of
the next few weeks.