What did it look like in the fish store?
Keep your powerheads covered but I would not turn down the flow, I would leave it where it always is and going to be. The nem will find its own spot in time. Just LEAVE IT ALONE in the conditions it will live in. If you lower the flow, it finds a nice place to settle in, then you change the flow it might start roaming again to find a better spot.
I think the mistake most folks make with anemones are to try to get it to do what they want it to do. This stresses the animal and a stressed animal will not find a happy spot.
JMO