150W for 12G?

[ssamick]

Ok guys i need your help. I.m getting ready to switch my 12g nano cube to metal halide. I have only softies in my tank right know. I would like to go with the 150 more for future use with larger tank down the road, but am I totally going to fry my tank right know. Should i just go with 70w? Any input would be great.
Thanks

 

[rockindacheeks]

i have a 150 on my 10 gallon and everything (mainly softies in my tank) are growing like crazy. I use an XM 20k.

 

[ssamick]

How high above the tank are you?

 

[rockindacheeks]

probably about 8"