Need lighting help for my 18g nano

[cstires]

I was wondering what type of lighting I could use for my 18g nano. It is made out of acrylic, and is 16x16x16, with a 4x13 external overflow connected to the back wall. I've attached some pictures of it.

I want to keep soft and LPS corals in the tank, as well as one or two nicely colored fish. Any suggestions on the fish would be appreciated as well.

Thanks in advance for your help!

 

[LBCBJ]

I use a 150w DE MH on my 18g, the Reef Optix III from Sunlight Supply with an IceCap ballast, the best I could find

 

[wav3form]

I have a 70 watt mh on my 10 gallon.

 

[cstires]

Do either of you have heat problems?