48" Tek (4x54) on a 120g. Enough light???

[iboard2]

I am looking at upgrading to 120g tank that will be primarily LPS and Zoos, all moderate light.

I currently have a factory stock 48" Tek (4x54) fixture with factory stock reflectors. Will this be enough light??

If it is not enough light will an Ice Cap ballast make it work?

Any advice from the lighting gurus would be appreciated!