250 watts would have been my choice--at the time of purchase I was greener then chaeto and the guys that sold me the system said I couldn't run them because of heat problems(they were in a coral life fixture under a wooden canopy.
Little did I know that eventually I would run the sump,refug and ballasts from the basement.
Kind of hard to change now--due to cost--besides I don't think I will ever have in LPS--not after what I have seen here at what you can aim for.