[lcstorc]

Well they are not terribly active and you will certainly see them sit on a branch for a significant period of time. Occasionally mine will roam the tank and then find a spot and just stay. Other than when sick mine have always gone after the thawed mysis. When did they eat last? I think I remember they ate yesterday or this morning so I would not get overly concerned off the bat. They are in new surroundings and may just be getting settled in.
What are your water parameters? They are fairly delicate so extra care should be taken to assure them of top quality water with am/ni/na/ph all at 0 and stable ph, temp, and salinity. They like low flow in the tank as well.
I would give them some time to settle in and keep offering the thawed mysis. Like I said, I feed twice a day, I know people who feed 3 times. Also I will try to find some links for you that I have on seahorse feeding stations. Perhaps you will find it helpful.