what kind of corals do you want to keep ? Heres a list of the lighting and what it can keep
MH- everything.
PC - softies,polyps,shrooms,LPS
VHO and MH is the the perfect combo IMO
They are only 110 altogether? Well, you will need to upgrade your lights if you want to keep most corals. You will want about 260 watts of power compact or VHO for a 55.