light questions for small frag tank

[edizzle]

I have a 12 gallon aquapod that I am using as a frag tank. I have the regular lights that come with the aquapod...I think they are the FT27W ATTINIC AND DAYLIGHT. I have egg crate set up for the frags and they are doing fine. I was wondering if better light would cause more growth or harm my tank because its a smaller tank.
I was interested in getting SunPod HQI Metal Halide Fixtures
-70 watt 14,000k
-150 watt 14,000k
-250 WATT 14,000K
Any thoughts? Would corals be harmed if to close to top of tank?
Here is a pic of the tank as is...