6 Bulb ATI Sunpower Too Much for 55gal

[mmaattppllaayy]

I have a RR55 from deep blue and found a good deal locally for a 48" 6 bulb ATI Sunpower. Is that light too much for a 55 mixed reef? I planned on hanging it 8in above the top of the tank. If need be would it hurt the ballasts to remove 2 bulbs for an extended period of time?

 

[TheWhiteFord]

How deep is your 55?

 

[mmaattppllaayy]

Standard size. 20" I believe.