250W on 120g

[newsalt]

I'm upgrading my MH lighting from two 175W 14k's on ARO 175W electronic ballasts to tow 250W 14k's on ARO 250W electronic ballasts.

My tank is a Perfecto 120g that is 60"L x 18"W x 26"H. I have a mixed reef with some SPS (acros, milleporas), LPS and softies. The bulbs will be about 9" from the surface of the water. Do I need to acclimate all the corals to the new wattage lights? If I have to, how should I do it? Should I run only one bulb for a week or so, then introduce the second? I need some advice.

Currently, my SPS are up high in the tank. Am I going to have to lower then under the new lighting?

Thanks

[Ti]

yeh some acclimation is a good idea

[CapnKick]

You should probably acclimate by starting your new lights on a shorter cycle and raised higher in your tank. Gradually increase the light cycle then gradually lower the lights to your intended permanent height. Then you won't have to move your corals around. Watch your corals (and water temp) closely at the new height/cycle. At any sign of degredation, raise the lights and start over.

[ken6217]

You can go to the hardware store and buy fiberglass window screening. Cut it into sheets and place on top of the tank. Each day or so you lift off another layer. I have not done it myself, but know people tha thave.
Ken